For a shooter, the initial velocity of a bullet (projectile) is perhaps the most important of all the quantities considered in internal ballistics.

Indeed, this quantity depends longest range shooting, direct shot range, i.e. the greatest range of direct fire at visible targets, at which the height of the trajectory of the bullet does not exceed the height of the target, the time of movement of the bullet (projectile) to the target, the impact of the projectile on the target and other indicators.

That is why it is necessary to pay attention to the very concept of the initial speed, to the methods for determining it, to how the initial speed changes when the parameters change. internal ballistics and when changing shooting conditions.

A bullet, when fired from small arms, starting to move along the bore under the action of powder gases faster and faster, reaches its top speed a few centimeters from the muzzle.

Then, moving by inertia and meeting the resistance of the air, the bullet begins to lose its speed. Therefore, the speed of the bullet changes all the time. Given this circumstance, it is customary to fix the speed of a bullet only in some specific phases of its movement. Usually fix the speed of the bullet when it leaves the bore.

The speed of the bullet at the muzzle of the barrel at the moment it leaves the bore is called the muzzle velocity.

For the initial speed, the conditional speed is taken, which is slightly more than the muzzle and less than the maximum. It is measured by the distance that a bullet could cover in 1 second after leaving the bore if neither air resistance nor its gravity acted on it. Since the speed of a bullet at some distance from the muzzle differs little from the speed when it leaves the bore, in practical calculations it is usually considered that the bullet has the highest speed at the moment of departure from the bore, i.e. that the muzzle velocity of the bullet is the greatest (maximum) speed.

The initial speed is determined empirically with subsequent calculations. The value of the initial velocity of the bullet is indicated in the firing tables and in the combat characteristics of the weapon.

So, when firing from a 7.62 mm magazine rifle of the Mosin system mod. 1891/30 the muzzle velocity of a light bullet is 865 m/s, and that of a heavy bullet is 800 m/s. When firing from a 5.6 mm TOZ-8 small-caliber rifle, the initial velocity of a bullet of various batches of cartridges varies between 280-350 m / s.

The value of the initial velocity is one of the most important characteristics of not only cartridges, but also the combat properties of weapons. However, it is impossible to judge the ballistic properties of a weapon by only one initial bullet velocity. With an increase in the initial speed, the range of the bullet, the range of a direct shot, the lethal and penetrating effect of the bullet increases, and the influence of external conditions on its flight also decreases.

The value of the muzzle velocity depends on the length of the barrel of the weapon; bullet mass; mass, temperature and humidity of the powder charge of the cartridge, the shape and size of the powder grains and the loading density.

The longer the barrel of a small arms weapon, the longer the powder gases act on the bullet and the higher the muzzle velocity of the bullet.

It is also necessary to consider the muzzle velocity of the bullet in combination with its mass. It is very important to know how much energy the bullet has, what work it can do.

It is known from physics that the energy of a moving body depends on its mass and speed. Therefore, the greater the mass of the bullet and the speed of its movement, the greater the kinetic energy of the bullet. With a constant barrel length and a constant mass of the powder charge, the initial velocity is greater, the smaller the mass of the bullet. An increase in the mass of the powder charge leads to an increase in the amount of powder gases, and, consequently, to an increase in the maximum pressure in the bore and an increase in the muzzle velocity. The greater the mass of the powder charge, the greater the maximum pressure and muzzle velocity of the bullet.

The length of the barrel and the mass of the powder charge increase when designing small arms samples to the most rational sizes.

With an increase in the temperature of the powder charge, the burning rate of the powder increases, and therefore the maximum pressure and the initial speed of the bullet increase. As the charge temperature decreases, the initial speed decreases. An increase (decrease) in initial velocity causes an increase (decrease) in the range of the bullet. In this regard, when shooting, it is imperative to take into account range corrections for air and charge temperature (charge temperature is approximately equal to air temperature).

With an increase in the humidity of the powder charge, its burning rate and the initial speed of the bullet decrease.

The shape and size of the powder have a significant impact on the burning rate of the powder charge, and hence on the muzzle velocity of the bullet. They are selected accordingly when designing weapons.

Loading density is the ratio of the mass of the charge to the volume of the sleeve with the inserted pool (charge combustion chambers). With a very deep landing of the bullet, the loading density increases significantly, which can lead to a sharp pressure jump when fired and, as a result, to a rupture of the barrel, so such cartridges cannot be used for shooting. With a decrease (increase) in the loading density, the initial velocity of the bullet increases (decreases).

The penetrating effect of a bullet (tables 1 and 2) is characterized by its kinetic energy(live force). The kinetic energy that the powder gases impart to the bullet at the moment it leaves the bore is called muzzle energy. Bullet energy is measured in joules.

Table 1
Penetrating action of a light bullet 7.62 mm sniper repeating rifle
Mosin system arr. 1891/30 (when shooting at distances up to 100 m)

RIFLE bullets have tremendous kinetic energy. So, the muzzle energy of a light bullet when firing from a rifle of the 1891/30 model. is equal to 3600 J. How great is the energy of the bullet, it can be seen from the following: in order to obtain such energy in such a short period of time (not by firing), a machine with a power of 3000 hp would be required. With.

From all that has been said, it is clear what great practical significance a high muzzle velocity and the muzzle energy of a bullet dependent on it has for shooting. With an increase in the initial velocity of the bullet and its muzzle energy, the firing range increases; the trajectory of the bullet becomes more sloping; the influence of external conditions on the flight of a bullet is significantly reduced; bullet penetration increases.

At the same time, the value of the initial velocity of a bullet (projectile) is greatly influenced by the wear of the bore. During operation, the barrel of the weapon undergoes significant wear. This is facilitated by a number of reasons of a mechanical, thermal, gas-dynamic and chemical nature.

First of all, the bullet, when passing through the bore, due to high friction forces, rounds off the corners of the rifling fields and abrades the inner walls of the bore. In addition, particles of powder gases moving at high speed hit with force the walls of the bore, causing the so-called hardening on their surface. This phenomenon consists in the fact that the surface of the bore is covered with a thin crust with fragility gradually developing in it. The elastic deformation of the barrel expansion that occurs during the shot leads to the appearance of small cracks on the inner surface of the metal.

The formation of such cracks is also facilitated by the high temperature of the powder gases, which, due to their very short action, cause partial melting of the bore surface. Large stresses arise in the heated metal layer, which ultimately lead to the appearance and growth of these small cracks. The increased fragility of the surface layer of the metal and the presence of cracks on it lead to the fact that the bullet, when passing through the bore, produces metal chips at the cracks. The wear of the barrel is also greatly facilitated by the soot remaining in the bore after the shot. It is the remains of the combustion of the primer composition and gunpowder, as well as metal scraped off from the bullet or smelted from it, pieces of the case mouth torn off by gases, etc.

The salts present in soot have the ability to absorb moisture from the air, dissolve in it and form solutions that, reacting with the metal, lead to its corrosion (rust), the appearance of a rash in the bore, and then shells. All these factors lead to a change, destruction of the surface of the bore, which entails an increase in its caliber, especially at the bullet entry, and, of course, a decrease in its overall strength. Therefore, the noted change in the parameters during barrel wear leads to a decrease in the initial velocity of the bullet (projectile), as well as to a sharp deterioration in the combat of the weapon, i.e. to the loss of their ballistic qualities.

If during the time of Peter I the initial speed of the cannonball reached 200 meters per second, then modern artillery shells fly much faster. The flight speed of a modern projectile in the first second is usually 800-900 meters, and some projectiles fly even faster, at a speed of 1000 or more meters per second. This speed is so great that the projectile, when it flies, is not even visible. Therefore, a modern projectile travels at 40 times the speed of a courier train and 8 times the speed of an airplane.

table 2
Penetrating action of a bullet of a 5.6 mm TOZ-8 small-caliber rifle (when firing at a distance of up to 25 m)

However, here we are talking about ordinary passenger aircraft and artillery shells flying from average speed.

If we take for comparison, on the one hand, the “slowest” projectile, and on the other hand, a modern jet aircraft, then the difference will not be so great, and, moreover, not in favor of the projectile: jet aircraft fly at an average speed of about 900 kilometers per hour , that is, about 250 meters per second, and a very "slow" projectile, for example, a projectile of the 152-mm Msta 2 C19 self-propelled howitzer, with the smallest charge, flies only 238 meters in the first second.

It turns out that a jet aircraft will not only not lag behind such a projectile, but will also overtake it.

A passenger plane flies about 900 kilometers in an hour. How much will a projectile flying several times faster than an airplane fly in an hour? It would seem that the projectile should fly about 4000 kilometers in an hour.

In fact, however, the entire flight artillery shell usually lasts less than a minute, the projectile flies 15-20 kilometers, and only for some guns - more.

What is the matter here? What prevents a projectile from flying as long and as far as an airplane flies?

The plane flies for a long time because the propeller pulls or the jet engine pushes it forward all the time. The engine runs for several hours in a row - until there is enough fuel. Therefore, the plane can fly continuously for several hours in a row.

The projectile receives a push in the channel of the gun, and then it flies by itself, no force pushes it forward anymore. From the point of view of mechanics, a flying projectile will be a body moving by inertia. Such a body, the mechanic teaches, must obey a very simple law: it must move in a straight line and uniformly, unless no other force is applied to it.

Does the projectile obey this law, does it move in a straight line?

Imagine that a kilometer away from us there is a target, for example, an enemy machine-gun point. Let's try to point the gun so that its barrel is pointed directly at the machine gun, then we'll fire a shot.

No matter how many times we shoot like this, we will never hit the target: every time the projectile will fall to the ground and burst, flying only 200-300 meters. If we continue the experiments, we will soon come to the following conclusion: in order to hit, you need to direct the barrel not at the target, but slightly above it.

It turns out that the projectile does not fly forward in a straight line: it descends in flight. What's the matter? Why does the projectile fly in a straight line? What is the force pulling the projectile down?

Artillery scientists of the late 16th and early 17th centuries explained this phenomenon in this way: a projectile flying obliquely upwards loses its strength, like a person climbing a steep mountain. And when the projectile finally loses its strength, it will stop in the air for a moment, and then fall down like a stone. The path of the projectile in the air seemed to the artillerymen of the 16th century as shown in the figure.

Nowadays, all people who have studied physics, knowing the laws discovered by Galileo and Newton, will give a more correct answer: gravity acts on a flying projectile and makes it descend during the flight. After all, everyone knows that a thrown stone does not fly straight, but describes a curve and, having flown a short distance, falls to the ground. Ceteris paribus, the stone flies the farther, the stronger it is thrown, the greater the speed it received at the moment of the throw.

Let's put a tool in place of a person throwing a stone, and replace the stone with a projectile; like any flying body, the projectile will be attracted to the ground during the flight and, therefore, move away from the line along which it was thrown, this line is called in artillery the line of throw, and the angle between this line and the horizon of the gun is the throw angle.

If we assume that only the force of gravity acts on the projectile during its flight, then under the influence of this force in the first second of the flight the projectile will fall by approximately 5 meters (more precisely - by 4.9 meters), in the second - by almost 15 meters (more precisely - by 14.7 meters) and every next second the falling speed will increase by almost 10 meters per second (more precisely, by 9.8 meters per second). This is the law of free fall of bodies discovered by Galileo.

Therefore, the line of flight of the projectile - the trajectory - is not straight, but exactly the same as for a thrown stone, similar to an arc.

In addition, one may wonder: is there a relationship between the angle of throw and the distance that the projectile flies?

Let's try to fire the gun once with the barrel horizontal, another time with a throw angle of 3 degrees, and a third time with a throw angle of 6 degrees.

In the first second of the flight, the projectile must move down from the throwing line by 5 meters. And this means that if the barrel of the gun lies on the machine 1 meter high from the ground and is directed horizontally, then the projectile will have nowhere to fall, it will hit the ground before the first second of the flight expires. The calculation shows that after 6 tenths of a second the projectile will hit the ground.

A projectile thrown at a speed of 600-700 meters per second, with a horizontal position of the barrel, will fly only 300 meters before falling to the ground. Now let's fire a shot at an angle of 3 degrees.

The line of throwing will no longer go horizontally, but at an angle of 3 degrees to the horizon.

According to our calculations, a projectile fired at a speed of 600 meters per second would have to rise to a height of 30 meters in a second, but gravity will take 5 meters away from it, and in fact the projectile will be at a height of 25 meters above the ground. After 2 seconds, the projectile, without gravity, would have already risen to a height of 60 meters, in fact, gravity will take another 15 meters in the second second of flight, and only 20 meters. By the end of the second second, the projectile will be at a height of 40 meters. If we continue the calculations, they will show that already at the fourth second the projectile will not only stop rising, but will begin to fall lower and lower. And by the end of the sixth second, having flown 3600 meters, the projectile will fall to the ground.

The calculations for firing at a 6-degree throw angle are similar to those we just did, but the calculations will take much longer: the projectile will fly for 12 seconds and fly 7200 meters.

Thus, we realized that the greater the angle of throw, the farther the projectile flies. But there is a limit to this increase in range: the projectile flies farthest if it is thrown at an angle of 45 degrees. If you further increase the angle of throw, the projectile will climb higher, but it will fall closer.

It goes without saying that the flight range will depend not only on the angle of throw, but also on the speed: the greater the initial velocity of the projectile, the further it will fall, all other things being equal.

For example, if you throw a projectile at an angle of 6 degrees with a speed of not 600, but 170 meters per second, then it will fly not 7200 meters, but only 570.

Consequently, the real highest muzzle velocity that can be achieved in a classic artillery gun cannot in principle exceed 2500–3000 m/s, and the actual firing range does not exceed several tens of kilometers. This is the peculiarity of artillery barrel systems (including small arms), realizing that humanity, in its pursuit of cosmic speeds and ranges, turned to the use of the jet propulsion principle.

Bullet speed is one of the most important characteristics of a weapon. Its value depends on a number of factors. These include the mass of the bullet, the length of the barrel of the weapon, and the energy transferred to the bullet, which depends on the mass of the powder charge. Moving along the bore under the influence of powder gases, the bullet reaches its maximum speed a few centimeters from the muzzle. This speed is called the initial speed and is indicated in the characteristics of the weapon. Naturally, for each weapon model, the bullet speed will be different. In this regard, it is possible to answer the question of how fast a bullet flies only by grading small arms according to their categories.

Pistols, revolvers, submachine guns

This category of weapons is characterized by a short barrel (it is often called short-barreled). It uses, as a rule, pistol cartridges equipped with a relatively small charge of gunpowder. In this regard, the initial velocity of the bullet is relatively low and averages 300-500 m/s. So, the initial speed of a bullet in a Makarov pistol (PM) is 315 m/s, in a TT pistol - 420 m/s.

Assault rifles, assault rifles

In this category of weapons, the so-called intermediate cartridge is mainly used. The initial speed of a bullet can reach an average of 700-1000 m / s. For example, the muzzle velocity of a bullet in a Kalashnikov assault rifle is 720 m/s.

Rifles, sniper rifles, machine guns

Such weapons use reinforced ammunition, and this factor has a decisive influence on how fast the bullet flies. Its value can reach 1500 m/s. So, the muzzle velocity of the famous Mosin rifle of the 1891/30 model. was equal to 865 m / s, the speed of a bullet in a Dragunov sniper rifle is 830 m / s, and the Kalashnikov light machine gun (RPK) fires bullets with an initial speed of 960 m / s.

On my three magnums ("Diana 31", "Gamo Socom Carbine Luxe", "Hatsan Striker") and one "super" ("Hatsan mod 135"), the speeds were also quite consistent with them. Where did all these fantastic figures of 380-400-470 m/s m/s come from? The secret is in the use for advertising purposes of ultra-light, completely not designed for such power, but very fast bullets.

Pre-pumped pneumatics (PCP) are no exception. It is clear that by pushing an ultra-light bullet into the drum and working with the pump from the heart, it is possible to achieve speeds exceeding 400 meters per second, almost at the level of a smooth-bore firearm. However, PCP owners use the right ammunition for their weapons and optimize the pressure (the so-called "plateau") or set the gearbox to again optimal performance. Depending on the caliber, the weapon gives out from 220 to about 320 m / s, and the more powerful it is, the lower the speed, and the bullets are heavier! In addition, the silencers installed on most modern PCP rifles, like those on a firearm, only work correctly at subsonic (up to 330 m/s) speeds.

For hunting, the main thing is the stopping effect of the projectile. That is, with light high-speed bullets it’s not bad to break through the boards for a dispute, and the heavy one will get stuck in them, transferring all the destructive energy to the mass of the tree. The same is true of living flesh.

In principle, this could have ended - the truth was voiced, the culprits were named. But if you really want to get to the bottom of the issue, and most importantly, decide on the characteristics of your specific rifle and choose the best ammunition for it, then you should continue reading this article. It will be interesting - then I will give examples of calculating the real indicators of pneumatic weapons.

The formula for calculating the energy, speed and mass of a bullet

Now we will conduct a "session of exposing black advertising magic." To do this, we will resort to the help of exact sciences - mathematics, physics, as well as more narrowly specialized ballistics ( full version of this article and other specialized materials on the features of shooting and hunting with pneumatics, read on my website arbalet-airgun.ru).

We will rely on the energy ("power") indicators officially cited by rifle manufacturers, which, unlike high-speed ones, are quite objective. The fact is that the weapons legislation of most countries focuses specifically on them, and they don’t joke with such things. Secondly, if meters per second is perfectly imagined by most people, then with all sorts of different joules, not everything is so smooth. It’s like for motorists: the maximum speed in km / h (by the way, is also always too high) is understandable to any "blonde", but with Newton meters of torque there are already problems.

There is a fundamental formula E = mv 2 /2, where "E" is energy, "m" is mass, and "v" is speed. That is, all these quantities are interconnected and depend on each other. We will carry out calculations of real indicators air rifles with different energy levels. Of the spring-piston 4.5 mm, we will focus on the license-free version up to 7.5 joules, the “magnums” - 20 and 25 joules, as well as the “supermagnums” - 30 J. We will consider weapons with pre-pumping (PCP) already in three main calibers - 4.5 (.177), 5.5 (.22) and 6.35 (.25) mm; 37, 53 and 60 joules, respectively

So, what kind of bullets do airgun manufacturers have in mind when they give fantastic speed ratings for advertised rifles...

A live cartridge for small arms consists of a bullet, a powder charge, a cartridge case and a primer (Scheme 107).

Scheme 107. Live cartridge

Sleeve designed to connect together all the elements of the cartridge, to prevent the breakthrough of powder gases when fired (obturation) and to save the charge.

The sleeve has a muzzle, slope, body and bottom (see diagram 107). At the bottom of the cartridge case there is a primer seat with a baffle, anvil and seed holes (Scheme 108). The anvil protrudes into the capsule socket, which is made from the outer surface of the bottom of the sleeve. On the anvil, the percussion composition of the primer is broken with a striker to ignite it, through the seed holes the flame from the primer penetrates to the powder charge.

Capsule designed to ignite a powder charge and is a cup-cap, at the bottom of which an impact composition is pressed, covered with a foil circle (see diagram 107). To ignite gunpowder, so-called initiating substances are used, which are highly sensitive and explode from mechanical impact.

The cap, which serves to assemble the elements of the primer, is inserted into the capsule socket with some tightness in order to eliminate the breakthrough of gases between its walls and the walls of the capsule socket. The bottom of the cap is made strong enough so that it does not break through the striker's striker and does not break through from the pressure of powder gases. The capsule cap is made of brass.

The impact composition ensures trouble-free ignition of the powder charge. Mercury fulminate, potassium chlorate and antimonium are used to prepare the shock composition.

Mercury fulminate Hg(ONC) 2 is the initiating agent in the shock composition. Advantages of mercury fulminate: preservation of its qualities during long-term storage, reliability of action, ease of ignition and comparative safety. Disadvantages: intense interaction with the metal of the barrel, which contributes to increased corrosion of the bore, amalgamation (mercury coating) of the primer cap, which leads to its spontaneous cracking and breakthrough of powder gases. To eliminate the last drawback, the inner surface of the cap is varnished.

Potassium chlorate KClO 3 is an oxidizing agent in the impact composition, ensures complete combustion of the components, increases the combustion temperature of the impact composition and facilitates the ignition of gunpowder. It is a colorless crystalline powder.

Antimony Sb 2 S 3 is a combustible in the impact composition. It is a black powder.

The percussion composition of the rifle cartridge primer contains: mercury fulminate 16%, potassium chlorate 55.5% and antimony 28.5%.

The foil circle protects the primer composition from destruction during cartridge shaking (during transportation, supply) and from moisture. The foil circle is varnished with shellac-rosin varnish.

The capsule is pressed into the capsule sockets in such a way that the foil covering the capsule composition lays stress-free on the anvil (Scheme 109).



Scheme 108. Diagram of a capsule socket with a capsule:

1 - anvil



Scheme 109. Capsule:

1 - cap; 2 - shock composition; 3 - foil circle

The burning rate of smokeless powder and the quality of the shot depend to a large extent on the quality of the firing of the primer. The capsule must form a flame of a certain length, temperature and duration. These qualities are united by the term "flame force". But capsules, even of very good quality, may not give the necessary flame force if the striker hits badly. For a full-fledged flash, the impact energy should be 0.14 kg m. The impact mechanisms of modern sniper rifles have such energy. But for the full ignition of the warhead of the primer, the shape and size of the striker are also important. With a normal striker and a strong mainspring of a cleaned percussion mechanism, the flame force of the primer is constant and ensures stable ignition of the powder charge. With a rusty, dirty, worn trigger mechanism, the energy of impact on the primer will be different, with pollution, the striker output for impact will be small, therefore, the force of the flame will be different (Scheme 110), the combustion of gunpowder will be uneven, the pressure in the barrel will change from shot to shot ( more - less - more), and do not be surprised if an uncleaned weapon suddenly gives noticeable "separations" up and down.



Scheme 110. Flame force of identical capsules in different conditions:

A - a striker of the correct shape and size with the necessary impact energy;

B - very sharp and thin striker;

B - normal-shaped striker with low impact energy

Powder charge is intended for the formation of gases that eject a bullet from the bore. The source of energy when fired is the so-called propellant powder, which has an explosive transformation with a relatively slow increase in pressure, which makes it possible to use them for throwing bullets and projectiles. In the modern practice of rifled barrels, only smokeless powders are used, which are divided into pyroxylin and nitroglycerin powders.

Pyroxylin powder is made by dissolving a mixture (in certain proportions) of wet pyroxylin in an alcohol-ether solvent.

Nitroglycerin powder is made from a mixture (in certain proportions) of pyroxylin with nitroglycerin.

The following are added to smokeless powders: a stabilizer - to protect the powder from decomposition, a phlegmatizer - to slow down the burning rate, and graphite - to achieve flowability and eliminate sticking of the powder grains.

Pyroxylin powders are used mainly in ammunition for small arms, nitroglycerin, as more powerful ones, in artillery systems and grenade launchers.

When a powder grain burns, its area decreases all the time, and, accordingly, the pressure inside the barrel decreases. In order to equalize the working pressure of the gases and provide a more or less constant grain burning area, powder grains are made with internal cavities, namely, in the form of a hollow tube or ring. Grains of such gunpowder burn simultaneously from both the inner and outer surfaces. The decrease in the outer burning surface is offset by the increase in the inner burning surface, so that the total area remains constant.

FIRE PROCESS IN THE SHORE

The powder charge of a rifle cartridge weighing 3.25 g burns out in about 0.0012 s when fired. When the charge is burned, about 3 calories of heat are released and about 3 liters of gases are formed, the temperature of which at the time of the shot is 2400-2900 ° C. The gases, being highly heated, exert high pressure (up to 2900 kg / cm 2) and eject a bullet from the barrel at a speed of over 800 m / s. The total volume of incandescent powder gases from the combustion of the powder charge of a rifle cartridge is approximately 1200 times greater in volume than was the powder before the shot.

A shot from small arms occurs in the following order, from the impact of the striker on the primer of a live cartridge locked in the chamber, its initiating substance, sandwiched between the sting of the striker and the anvil of the cartridge case, ignites, this flame is ejected through the seed holes to the powder charge and covers the grains of gunpowder. The entire charge of gunpowder ignites almost simultaneously. Formed during the combustion of gunpowder a large number of gases creates a high pressure on the bottom of the bullet and the walls of the sleeve. This gas pressure creates a stretch in the width of the walls of the sleeve (while maintaining their elastic deformation), and the sleeve is pressed tightly against the walls of the chamber, preventing, like a shutter, the breakthrough of powder gases back to the bolt.

As a result of the pressure of gases on the bottom of the bullet, it moves from its place and crashes into the rifling. Rotating along the grooves, the bullet moves along the bore with a continuously increasing speed and is ejected in the direction of the axis of the bore.

The pressure of the gases on the opposite walls of the barrel and the chamber also causes their slight elastic deformation and is mutually balanced. The pressure of the gases on the bottom of the cartridge case of the cartridge locked by the bolt causes the weapon to move backward. This phenomenon is called recoil. According to the laws of mechanics, recoil increases with an increase in the powder charge, the weight of the bullet, and with a decrease in the dead weight of the weapon.

In all countries, they try to make ammunition very High Quality. Despite this, from time to time there is a manufacturing defect or ammunition deteriorates from improper storage. Sometimes, after hitting the primer with a striker, a shot will not follow or it happens with some delay. In the first case, there is a misfire, in the second - a protracted shot. The cause of a misfire is most often dampness of the percussion composition of the primer or powder charge, as well as a weak impact of the striker on the primer. Therefore, it is necessary to protect the ammunition from moisture and keep the weapon in good condition.

A protracted shot is a consequence of the slow development of the process of ignition of the powder charge. Therefore, after a misfire, do not immediately open the shutter. Usually, after a misfire, five or six seconds are counted, and only after that the shutter is opened.

During the combustion of a powder charge, only 25-30% of the released energy is spent as useful work on ejecting a bullet. To perform secondary work - cutting into rifling and overcoming the friction of a bullet when moving along the bore, heating the walls of the barrel, cartridge case and bullet, moving moving parts into automatic weapons, emission of gaseous and unburned part of the powder - up to 20% of the energy of the powder charge is used. About 40% of the energy is not used and is lost after the bullet leaves the bore.

The task of the powder charge and the barrel is to accelerate the bullet to the required flight speed and give it lethal combat energy. This process has its own characteristics and occurs in several periods.

The preliminary period lasts from the beginning of the burning of the powder charge to the complete cutting of the shell of the bullet into the rifling of the barrel. During this period, the gas pressure is created in the barrel bore, which is necessary in order to move the bullet from its place and overcome the resistance of its shell to cutting into the rifling of the barrel. This pressure is called forcing pressure, it reaches 250-500 kg / cm 2, depending on the geometry of the rifling, the weight of the bullet and the hardness of its shell. The burning of the powder charge in this period occurs in a constant volume, the shell cuts into the rifling instantly, and the movement of the bullet along the barrel begins immediately when the forcing pressure is reached in the barrel bore. Gunpowder at this time still continues to burn.

The first, or main, period lasts from the beginning of the movement of the bullet until the moment of complete combustion of the powder charge. During this period, the combustion of gunpowder occurs in a rapidly changing volume. At the beginning of the period, when the speed of the bullet along the bore is not yet high, the amount of gases grows faster than the volume of space between the bottom of the bullet and the bottom of the cartridge case (punch space), the gas pressure rises rapidly and reaches its maximum value - 2800-3000 kg / cm 2 (see diagrams 111, 112). This pressure is called maximum pressure. It is created in small arms when a bullet travels 4-6 cm of the path. Then, due to the rapid increase in the speed of the bullet, the volume of the bullet space increases faster than the influx of new gases, the pressure in the barrel begins to fall and by the end of the period it reaches approximately 3/4 of the desired initial velocity of the bullet. The powder charge burns out shortly before the bullet leaves the bore.




Scheme 111. Change in gas pressure and increase in bullet speed in the barrel of a rifle of the 1891-1930 model



Scheme 112. Change in gas pressure and bullet velocity in the barrel of a small-caliber rifle

The second period lasts from the moment of complete combustion of the powder charge until the moment the bullet leaves the bore. With the beginning of this period, the influx of powder gases stops, however, highly compressed and heated gases continue to expand and, continuing to put pressure on the bullet, increase its speed. The pressure drop in the second period occurs quite quickly and at the muzzle is 570-600 kg/cm 2 for the rifle.

The third period, or the period of aftereffect of gases, lasts from the moment the bullet leaves the bore until the moment the action of powder gases on the bullet ceases. During this period, powder gases flowing out of the bore at a speed of 1200-2000 m/s continue to act on the bullet and tell it extra speed. The bullet reaches its maximum, maximum, speed at the end of the third period at a distance of several tens of centimeters from the muzzle of the barrel. This period ends at the moment when the pressure of the powder gases at the bottom of the bullet is balanced by air resistance.

What is the practical significance of all of the above? Look at the chart 111 for a 7.62mm rifle. Based on the data of this graph, it becomes clear why the length of the rifle barrel practically does not make sense to make it more than 65 cm. If it is made longer, the speed of the bullet increases very slightly, and the dimensions of the weapon increase senselessly. It becomes clear why a three-line rifle with a barrel length of 47 cm and a bullet speed of 820 m/s has almost the same fighting qualities as a three-line rifle with a barrel length of 67 cm and an initial bullet speed of 865 m/s.

A similar picture is observed in small-caliber rifles (diagram 112) and especially in weapons chambered for a 7.62-mm automatic cartridge of the 1943 model.

The length of the rifled part of the barrel of the AKM assault rifle is only 37 cm with an initial bullet speed of 715 m/s. The length of the rifled part of the barrel of a Kalashnikov light machine gun firing the same cartridges is 54 cm, 17 cm more, and the bullet accelerates slightly - the muzzle velocity of the bullet is 745 m / s. But for rifles and machine guns, the barrel has to be made elongated for greater accuracy of combat and for lengthening the aiming line. These parameters provide improved shooting accuracy.

INITIAL SPEED OF THE BULLET

The initial speed is one of the most important characteristics of the combat properties of weapons. With an increase in the initial speed, the range of the bullet, the range of a direct shot, the lethal and penetrating effect of the bullet increases, and the influence of external conditions on its flight also decreases. In particular, the faster the bullet flies, the less it is blown to the side by the wind. The value of the initial velocity of the bullet must be indicated in the firing tables and in the combat characteristics of the weapon.

The value of the muzzle velocity of a bullet depends on the length of the barrel, the weight of the bullet, the weight, temperature and humidity of the powder charge, the shape and size of the grains of the powder, and the loading density.

The longer the barrel, the longer the powder gases act on the bullet and the greater (within known technical limits, see earlier) the initial velocity.

With a constant barrel length and a constant weight of the powder charge, the initial velocity is greater, the lower the weight of the bullet.

A change in the weight of the powder charge leads to a change in the amount of powder gases, and, consequently, to a change in the maximum pressure in the bore and the initial velocity of the bullet. The more gunpowder, the more pressure and the more the bullet accelerates along the barrel.

The length of the barrel and the weight of the powder charge are balanced according to the above graphs (schemes 111, 112) of the internal fire processes in the rifle barrel during the design and layout of weapons to the most rational sizes.

With an increase in external temperature, the burning rate of gunpowder increases, and therefore the maximum pressure and initial speed increase. When the outside temperature drops, the initial speed decreases. In addition, when the outside temperature changes, the temperature of the trunk also changes, and more or less heat is needed to heat it. And this, in turn, affects the change in pressure in the barrel and, accordingly, the initial velocity of the bullet.

One of the old snipers in the memory of the author in a specially sewn bandolier carried a dozen rifle cartridges under his arm. When asked what it matters, the elderly instructor replied, "Very great importance. You and I were both shooting at 300 meters now, but your spread went vertically up and down, but mine didn’t. Because the gunpowder in my cartridges will warm up to 36 degrees under the arm, and yours in the pouch froze to minus 15 (it was in winter). You shot the rifle in the fall at plus 15, in total the difference is 30 degrees. You shoot with rapid fire, and your barrel is hot, so your first bullets go lower and the second bullets go higher. And I shoot gunpowder at the same temperature all the time, so everything flies as it should."

An increase (decrease) in the initial speed causes an increase (decrease) in the firing range. The differences in these values ​​are so significant that in the practice of hunting shooting from smoothbore guns, summer and winter barrels of different lengths are used (winter barrels are usually 7-8 cm longer than summer ones) to achieve the same range of a shot. In sniper practice, range corrections for air temperature are necessarily made according to the relevant tables (see earlier).

With an increase in the humidity of the powder charge, its burning rate decreases and, accordingly, the pressure in the barrel and the initial speed decrease.

The burning rate of gunpowder is directly proportional to the pressure surrounding it. In the open air, the burning rate of smokeless rifle powder is approximately 1 m / s, and in the closed space of the chamber and barrel, due to increased pressure, the burning rate of gunpowder increases and reaches several tens of meters per second.

The ratio of the weight of the charge to the volume of the sleeve with the inserted pool (charge combustion chamber) is called the loading density. The more the gunpowder is "rammed" into the case, which happens when the gunpowder is overdosed or the bullet is seated too deep, the more the pressure and combustion rate increase. This sometimes results in a sudden surge in pressure and even in the detonation of the powder charge, which can lead to a rupture of the barrel. The loading density is made according to complex engineering calculations and for a domestic rifle cartridge is 0.813 kg/dm3. With a decrease in loading density, the burning rate decreases, the time it takes the bullet to travel through the barrel increases, which, paradoxically, leads to a rapid overheating of the weapon. For all these reasons, reload live ammunition prohibited!

FEATURES OF ACTIVATION OF SMALL-CALE (5.6 MM) SIDE-FIRE CARTRIDGES

The capsular charge in side-fire cartridges is pressed from the inside into the rim of the cartridge case (the so-called Flaubert cartridge), and the impact with the striker for the shot is carried out, respectively, not in the center, but along the rim of the bottom of the cartridge case. For small-caliber cartridges with a solid lead shellless bullet, the powder charge is very small and with a low loading density (gunpowder is poured up to half the volume of the sleeve). The pressure of powder gases is insignificant and ejects a bullet with an initial speed of 290-330 m/s. This is done because more pressure can pull the soft lead bullet off the rifling. For sports purposes and biathlon, the above bullet speed is quite enough. But at a low external air temperature, with even a slight lack of powder, the pressure in a small-caliber barrel can drop sharply, when the pressure drops, the gunpowder stops burning, and there are cases when, at minus 20 ° C and below, the bullets simply get stuck inside the barrel. Therefore, in winter time at negative temperatures, it is recommended to use cartridges of increased power "Extra" or "Biathlon".

BULLET THEORY

The bullet is the striking element. The range of its flight depends on the specific gravity of the material from which it is made.

In addition, this material must be ductile for cutting into the rifling of the barrel. This material is lead, which has been used to make bullets for several centuries. But a soft lead bullet, with an increase in the powder charge and pressure in the barrel, breaks off the rifling. The initial speed of a solid lead bullet of the Berdan rifle did not exceed 420-430 m / s, and this was the limit for a lead bullet. Therefore, the lead bullet began to be enclosed in a shell of a more durable material, or rather, molten lead was poured into this durable shell. Such bullets used to be called two-layer. With a two-layer device, the bullet retained as much weight as possible and had a relatively strong shell.

The shell of the bullet, made of a material more durable than the lead that filled it, did not allow the bullet to break off the rifling at strong pressures inside the barrel and made it possible to sharply increase the initial velocity of the bullet. Moreover, with a strong shell, the bullet deformed less when it hit the target, and this improved its penetrating (piercing) effect.

Bullets, consisting of a dense shell and a soft core (lead fill), appeared in the 70s of the XIX century after the invention of smokeless powder, which provides increased working pressure in the barrel. This was a breakthrough in the development of firearms, which made it possible in 1884 to create the world's first and very successful famous machine gun "Maxim". The shell bullet provided increased survivability of rifled barrels. The fact is that soft lead "enveloped" on the walls of the barrel, clogged the rifling, which sooner or later caused the barrels to swell. In order to prevent this from happening, lead bullets were wrapped in salted thick paper, and still it didn’t help much. In modern small-caliber weapons that fire lead shellless bullets, the bullets are coated with special technical grease to avoid lead envelopment.

The material from which the shell of the bullet is made must be ductile enough so that the bullet can cut into the rifling, and strong enough so that the bullet does not break off when moving along the rifling. In addition, the material of the shell of the bullet should have as low a coefficient of friction as possible in order to wear the barrel walls less and be resistant to rust.

All these requirements are best met by cupronickel - an alloy of 78.5-80% copper and 21.5-20% nickel. Cupronickel jacketed bullets have proven themselves better than any other bullets. But cupronickel was very expensive to mass-produce ammunition.

Bullets with cupronickel sheath were produced in pre-revolutionary Russia. During the First World War, in the absence of nickel, the shells of bullets were forced to be made of brass. During the civil war, both the Reds and the Whites made ammunition from whatever they had. The author had to see the cartridges of those years with bullet shells made of brass, thick copper and mild steel.

In the Soviet Union, cupronickel-coated bullets were produced until 1930. In 1930, instead of cupronickel, low-carbon mild steel clad (coated) with tompak began to be used for the manufacture of shells. Thus, the shell of the bullet became bimetallic.

Tompac is an alloy of 89-91% copper and 9-11% zinc. Its thickness in the bimetallic shell of the bullet is 4-6% of the shell wall thickness. The bimetallic shell of the bullet with a tombac coating basically met the requirements, although it was somewhat inferior to cupronickel shells.

Due to the fact that the manufacture of tompak coatings requires scarce non-ferrous metals, before the war in the USSR they mastered the production of shells from cold-rolled low-carbon steels. These shells were covered with a thin layer of copper or brass by electrolytic or contact method.

The core material in modern bullets is soft enough to ease the bullet into the rifling and has a fairly high melting point. For this, an alloy of lead and antimony is used in a ratio of 98-99% lead and 1-2% antimony. The admixture of antimony makes the lead core somewhat stronger and increases its melting point.

The above-described bullet, which has a shell and a lead core (pouring), is called an ordinary one. Among ordinary bullets, there are solid ones, for example, a French solid tombac bullet (diagram 113), a French elongated solid aluminum bullet (4 in diagram 114), as well as lightweight ones with a steel core. The appearance of a steel core in ordinary bullets is caused by the requirement to reduce the cost of the bullet design by reducing the amount of lead and reducing the deformation of the bullet in order to increase the penetrating effect. Between the jacket of the bullet and the steel core is a lead jacket to facilitate cutting into the rifling.

Scheme 113 French solid tombac bullet



Scheme 114. Ordinary bullets:

1 - domestic light, 2 - German light; 3 - domestic heavy; 4 - French solid; 5 - domestic with a steel core; 6 - German with a steel core; 7 - English; 8 - Japanese A - annular groove - knurling for fastening a bullet in a sleeve

Until now, bullets of old manufacture are found in use. There are light bullets of the 1908 model with a cupronickel shell without an annular knurling for fixing the bullet in the sleeve (scheme 115) and a light bullet of the 1908-1930 model. with a steel howl, a shell clad with tombac, having an annular knurling for better fixing of the bullet in the muzzle of the cartridge case when assembling the cartridge (A in diagram 114).

Scheme 115. Light bullet of the 1908 model without knurling

The materials from which the shell of the bullet is made wear out the barrel in different ways. The main cause of barrel wear is mechanical abrasion, and therefore the harder the shell of the bullet, the more intense the wear. Practice has shown that when firing from the same type of weapon with bullets with different shells made in different time at different plants, the survivability of the trunk is different. When firing a bullet with a wartime steel jacket not clad with tompak, barrel wear increases sharply. The uncoated steel shell has a tendency to rust, which drastically reduces the accuracy of shooting. Such bullets were fired by the Germans in recent months Second World War.

In the design of a bullet, a head, leading and tail parts are distinguished (diagram 116).



Scheme 116. functional parts of a 1930 model bullet:

A - head, B - leading, C - tail streamlined

The head of a modern rifle bullet has a conical elongated shape. The faster the bullet, the

its head should be longer. This situation is dictated by the laws of aerodynamics. The elongated tapered nose of the bullet has less aerodynamic drag when flying in the air. For example, a lively blunt-pointed bullet of a three-linear rifle of the first model of production until 1908 gave a 42% decrease in speed on the way from 25 to 225 m, and a pointed bullet of the 1908 model on the same path - only 18%. In modern bullets, the length of the head of the bullet is selected in the range from 2.5 to 3.5 caliber weapons. The leading part of the bullet crashes into the rifling.

The purpose of the leading part is to give the bullet a reliable direction and rotational movement, as well as to tightly fill the grooves of the rifling of the bore in order to eliminate the possibility of a breakthrough of powder gases. For this reason, bullets are made in thickness with a larger diameter than the nominal caliber of the weapon (Table 38).

Table 38

Data of rifle cartridges of 7.62 mm caliber produced in the USSR at different times




As a rule, the leading part of the bullet is cylindrical, sometimes a slight taper is attached to the leading part of the bullet for smooth penetration. For a better direction of movement of the bullet along the bore and to reduce the likelihood of a breakdown from the rifling, it is more advantageous to have a longer length of the leading part, moreover, with its longer length, the accuracy of the battle increases. But with an increase in the length of the leading part of the bullet, the force required to cut the bullet into the rifling increases. This can lead to a transverse rupture of the shell. With regard to barrel survivability, protection of the shell from rupture and ensuring better air flow in flight, a shorter leading part is more advantageous.

A long leading part wears out the barrel more intensively than a short one. When firing an old Russian blunt-pointed bullet with a larger leading part, the survivability of the barrels was half as much as when firing a new pointed bullet of the 1908 model with a shorter leading part. In modern practice, the limits of the length of the leading part from 1 to 1.5 caliber sizes are accepted.

From the point of view of shooting accuracy, it is unprofitable to take the length of the leading part less than one diameter of the bore along the rifling grooves. Bullets shorter than the diameter of the bore along the rifling give a greater spread.

In addition, a decrease in the length of the leading part leads to the possibility of its breakdown from the rifling, to the incorrect flight of the bullet in the air and to the deterioration of its obturation. With a small length of the leading part of the bullet, gaps are formed between the bullet and the bottom of the rifling groove. Hot powder gases with solid particles of unburned gunpowder rush into these gaps at high speed, which literally “lick off” the metal and dramatically increase barrel wear. A bullet that does not go along the barrel tightly, but "walks" along the rifling, gradually "breaks" the barrel and degrades the quality of its further work.

The rational relationship between the length of the leading part of the bullet and the diameter of the bore along the grooves of the rifling is also selected depending on the material of the shell of the bullet. Bullets with a softer jacket material than steel may have a lead length slightly longer than the grooved diameter of the barrel. This value can be no more than 0.02 caliber for grooves.

The fastening of the bullet in the case is carried out by rolling or crimping the muzzle of the case into the annular knurling of the bullet, which is usually done closer to the front end of the leading part. The muzzle of steel sleeves rolled into knurling will not "remove chips" and deform the chamber when a cartridge is fed into it.

A lot depends on the fastening of the bullet in the sleeve. With a weak fastening, forcing pressure does not develop, with a very dense powder, it burns out in a constant volume of the sleeve, which causes a sharp jump in the maximum pressure in the barrel, up to rupture. When firing cartridges with different bullet rolling, there will always be a spread of bullets in height.

The tail of the bullet can be flat (like a light bullet of the 1908 model) or streamlined (like a heavy bullet of the 1930 model) (see diagram 116).

BALLISTICS OF A BULLET

At supersonic bullet speeds, when the main cause of air resistance is the formation of an air seal in front of the head, bullets with an elongated pointed nose are advantageous. A rarefied space is formed behind the bottom of the bullet, as a result of which a pressure difference appears on the head and bottom parts. This difference determines the resistance of the air to the flight of the bullet. The larger the diameter of the bottom of the bullet, the greater the rarefied space, and, naturally, the smaller the diameter of the bottom, the smaller this space is too. Therefore, the bullets are given a streamlined cone-shaped shank, and the bottom of the bullet is left as small as possible, but sufficient to fill it with lead.

From external ballistics, it is known that at a bullet speed greater than the speed of sound, the shape of the tail of the bullet has a relatively smaller effect on air resistance than the head of the bullet. With a high initial velocity of a bullet at firing distances of 400-450 m, the general aerodynamic pattern of air resistance for bullets with both a flat and a streamlined tail is approximately the same (A, B in diagram 117).



Scheme 117. Bullet ballistics different shapes at different speeds:

A - ballistics of a bullet with a tapered shank at high speeds;

B - ballistics of a bullet without a tapered shank at high and low speeds;

B - ballistics of a bullet with a tapered shank at low speeds:

1 - wave of compacted air; 2 - separation of the boundary layer; 3 - sparse space

The influence of the shape of the tail section on the magnitude of the air resistance force increases with decreasing bullet speed. The tail part in the form of a truncated cone gives the bullet a more streamlined shape, due to which, at low speeds, the area of ​​rarefied space and air turbulence behind the bottom of the flying bullet are reduced (B in diagram 117). Whirlwinds and the presence of an area of ​​reduced pressure behind the bullet lead to a rapid loss of bullet velocity.

The tapered tail section is more appropriate for heavy bullets used for firing at long distances, since at the end of the flight at long range bullet speed is slow. In modern bullets, the length of the tail conical part lies in the range of 0.5-1 caliber.

The total length of the bullet is limited by the conditions of its stability during flight. With the normal steepness of the rifling, the stability of the bullet in flight is ensured with its length not exceeding 5.5 calibers. A bullet of greater length will fly at the limit of stability, and even with natural turbulence of air currents, it can go somersault.

LIGHT AND HEAVY BULLETS. LATERAL LOAD OF THE BULLET

The lateral load of a bullet is the ratio of the bullet's weight to the cross-sectional area of ​​its cylindrical part.

a n \u003d q / S n (g / cm 2),

where q is the weight of the bullet in grams;

S n is the cross-sectional area of ​​the bullet in cm 2 .

How more weight bullets with the same caliber, the greater its transverse load. Depending on the magnitude of the transverse load, light and heavy bullets are distinguished. Ordinary bullets with a normal caliber (see below) a transverse load of more than 25 g / cm 2 and a weight of more than 10 g are called heavy, and normal caliber bullets with a weight of less than 10 g and a transverse load of less than 22 g / cm 2 are called lungs (Table 39).

Table 39

The main data of the light bullet of the 1908 model and the heavy bullet of the 1930 model




High lateral load bullets have a slower muzzle velocity than light bullets for the same maximum barrel pressure. Therefore, at short ranges, a light bullet gives a flatter trajectory than a heavy bullet (diagram 118). However, with an increase in the transverse load, the acceleration of the air resistance force decreases. And since the acceleration of the air resistance force acts in the opposite direction to the speed of the bullet, bullets with a greater transverse load slowly lose speed under the influence of air resistance. So, for example, a domestic heavy bullet at a distance of more than 400 m has a flatter trajectory than a light bullet (see diagram 118).



Scheme 118. Trajectories of light and heavy bullets when firing at different ranges

Of considerable importance is the fact that a heavy bullet has a tapered shank and its aerodynamics at low speeds are more perfect than the aerodynamics of a light bullet (see earlier).

For all these reasons, when reaching a distance of 500 m, a light bullet of the 1908 model begins to slow down, but a heavy one does not (Table 40).

Table 40

Bullet flight time, s



It has been established by practice that heavy bullets at distances of 400 m provide a more accurate fight and have a stronger effect on the target than light bullets. From rifles and machine guns, the maximum range of a heavy bullet is 5000 m, and a light bullet is 3800.

For ordinary infantry rifles, from which shooting by poorly trained shooters, as a rule, is carried out at distances up to 400 m, shooting with light bullets will be practical, because at this distance the trajectory of a light bullet will be flatter, and therefore more effective. But for snipers and machine gunners who need to reach a target at 800 m (and machine gunners further), it is more expedient and effective to shoot with heavy bullets.

For a better understanding of the process, we will give a ballistic interpretation of scheme 118. In order for a heavy bullet to hit the same point as a light one when firing at a distance of 200 m, it must be given a larger elevation angle when fired, that is, "raise" the trajectory by almost one or two centimeters .

If the rifle is shot with light bullets at a distance of 200 m, heavy bullets at the end of the distance will go one and a half to two centimeters lower (if the scope is set to fire light bullets). But at a distance of 400 m, the speed of a light bullet already drops faster than the speed of a heavy bullet, which has a more perfect aerodynamic shape. Therefore, at a distance of 400-500 m, the trajectories and points of impact of both bullets coincide. At longer distances, a light bullet loses speed even more than a heavy one. At a firing distance of 600 m, a light bullet hits the same point as a heavy one if it is fired at a higher elevation angle. That is, now it is necessary to raise the trajectory already when firing a light bullet. Therefore, when shooting from a rifle shot with heavy bullets, at a distance of 600 m, light bullets will go lower (actually by 5-7 cm). Heavy bullets at firing ranges over 400-500 m have a flatter trajectory and greater accuracy, so they are more preferable for firing at distant targets.

Light bullet sample 1908 has a transverse load of 21.2 g/cm 2 . heavy bullet sample 1930 - 25.9 g / cm 2 (Table 39).

The bullet of the 1930 model was made heavier by an elongated nose and a cone-shaped tail (b in diagram 119). Light bullet sample 1908-1930. has a conical recess in the tail section - The presence of this inner cone (and in the diagram 119) creates profitable terms for obturation of powder gases, since the tail of the bullet expands in diameter due to gas pressure and is tightly pressed against the walls of the bore.



Scheme 119. Light and heavy bullets:

a - a light bullet; b - heavy bullet:

1 - shell: 2 - core

This circumstance allows you to increase the service life of the barrel, because a light bullet cuts well into the rifling, presses against them and receives rotational motion even at a very low rifling height. Thus, the inner hollow cone of a light bullet, with its lower mass and inertia, increases the survivability of the barrels.

For the same reason, shooting with a light bullet from old rifles with worn-out barrels is more accurate and effective than shooting with heavy bullets. A heavy bullet, when passing through an old barrel, is “scraped off” by the unevenness of the shells from rust and fire, like a file, decreases in diameter and, when exiting the barrel, begins to “walk” in it. A light bullet is constantly expanded to the sides by its conical skirt and, while working in the barrel, is pressed against its inner walls.

Remember: shooting with a light bullet doubles the survivability of the barrels. From the new barrels, the quality of shooting (accuracy of battle) is better when shooting with a heavy bullet. From old, worn barrels, the quality of shooting is best when firing a light bullet with an internal tail cone.

Light bullets have the advantage of a flat trajectory up to a range of 400-500 m. Starting from a range of 400-500 m and more, a heavy bullet has advantages in all respects (bullet energy is greater, dispersion is less and the trajectory is flatter). Heavy bullets are deflected less by drift and wind, as much less as they weigh more than a light bullet (by about 1/4). At distances over 400 m, the probability of hitting when shooting with a heavy bullet is three times greater than when shooting with a light bullet.

When shooting at a distance of 100 m, heavy bullets go 1-2 cm lower than light ones.

The nose (top) of a heavy bullet of the 1930 model is painted yellow. The light bullet of the 1908 model has no special distinguishing marks.

BULLET ACTION ON TARGET. BULLET DAMAGE

The defeat of a living open target when it hits is determined by the lethality of the bullet. The lethality of a bullet is characterized by the live force of impact, that is, the energy at the moment of meeting with the target. Bullet energy E depends on the ballistic properties of the weapon and is calculated by the formula:

E \u003d (g x v 2) / S

where g is the weight of the bullet;

v is the speed of the bullet at the target;

S - free fall acceleration.

The greater the weight of the bullet and the greater its muzzle velocity, the greater the energy of the bullet. Accordingly, the energy of the bullet is greater the greater the speed of the bullet at the target. The speed of the bullet at the target is the greater, the more perfect its ballistic qualities, determined by the shape of the bullet and its streamlining. To inflict a defeat that incapacitates a person, a bullet energy of 8 kg m is sufficient, and to inflict the same defeat on a beast of burden, an energy of about 20 kg m is needed. flight. Bullets of sports small-caliber cartridges lose speed and energy very quickly. In practice, such a small-caliber bullet loses its guaranteed lethality at a distance of more than 150 m (Table 41).

Table 41

Ballistic data of a small-caliber bullet 5.6 mm



When firing at normal sighting distances, the bullets of all models of military small arms have a multiple energy reserve. For example, when firing a heavy bullet from a sniper rifle at a distance of 2 km, the energy of the bullet at the target is 27 kg m.

The effect of a bullet on living targets depends not only on the energy of the bullet. Of great importance are factors such as "side action", the ability of the bullet to deform, the speed and shape of the bullet. "Side action" - a blow to the sides - is characterized not only by the size of the wound itself, but also by the size of the affected tissue in the neighborhood of the wound. From this point of view, pointed long bullets have a large "lateral" effect due to the fact that a long bullet with a light warhead begins to "tumble" when it hits living tissue. The so-called "tumbling" bullets with a displaced center of gravity were known at the end of the last century and were repeatedly banned. international conventions due to the monstrous impact: a bullet tumbling through the body leaves behind a channel five centimeters in diameter, filled with crushed minced meat. In combined arms practice, the attitude towards them is ambivalent - these bullets, of course, kill on the spot, but in flight they go to the limit of stability and often begin to tumble even from strong gusts of wind. In addition, the penetrating effect on the target with tumbling bullets leaves much to be desired. For example, when firing such a bullet through a wooden door, the tumbling bullet makes through the door huge hole and that's where her energy ends. The target behind this door has a chance to survive.

The ability of the bullet to deform increases the affected area. Shellless lead bullets, when they enter the tissue of a living organism, are deformed in the front part and cause very severe injuries. In hunting practice, for shooting at a large animal from a rifled weapon, the so-called expansive unfolding semi-shell bullets are used. The leading part of these bullets and a little of the head part are enclosed in a shell, and the nose is left weakened, sometimes the lead fill "peeps" out of the shirt, sometimes this fill is covered with a cap, sometimes the counter body is made in the head part (Scheme 120). These bullets are sometimes torn apart when they meet the target and therefore in the old days were called explosive (this is a misnomer). The first samples of such bullets were made in the 70s of the XIX century in the Dum-Dum arsenal near Calcutta, and therefore the name Dum-Dum stuck to half-shell bullets of various calibers. In military practice, such bullets with a soft nose are not used due to a small penetrating effect.



Scheme 120. Expanding bullets:

1 - firm "Rose"; 2 and 3 - firms "Western"

The lethal effect of a bullet is greatly influenced by its speed. Man is 80% water. An ordinary pointed rifle bullet, when it hits a living organism, causes a so-called hydrodynamic shock, the pressure from which is transmitted in all directions, causing a general shock and severe destruction around the bullet. However, the hydrodynamic effect manifests itself when firing at live targets at a bullet speed of at least 700 m/s.

Along with the lethal action, the so-called "stopping action" of the bullet is also distinguished. A stopping action is the ability of a bullet, when it hits the most important organs, to quickly upset the functions of the enemy’s body so that he cannot actively resist. With a normal stopping action, a living target should be instantly disabled and immobilized. The stopping effect is of great importance at point-blank ranges and increases with the increase in the caliber of the weapon. Therefore, the calibers of pistols and revolvers are usually made larger than rifle ones.

For sniper shooting, usually performed at medium distances (up to 600 m), the stopping effect of a bullet does not really matter.

SPECIAL ACTION BULLETS

When conducting combat operations, it is impossible to do without special action bullets - armor-piercing, incendiary, tracer, etc.

Cartridges with armor-piercing bullets are designed to defeat the enemy behind armored shelters. Armor-piercing bullets differ from ordinary bullets in the presence of an armor core of high strength and hardness. Between the shell and the core is usually a soft lead jacket, which facilitates the insertion of a bullet into the rifling and protects the bore from intense wear. Sometimes armor-piercing bullets do not have a special jacket. Then the shell, being the body of the bullet, is made of a soft material. This is how the French armor-piercing bullet (3 in diagram 121) is arranged, consisting of a tombac case and a steel armor-piercing core. The nose of the armor-piercing bullet is painted black.



Scheme 121. Armor-piercing bullets:

1- domestic; 2 - Spanish; 3 - French

The armor-piercing effect of bullets is usually beneficial to combine with other types of action: incendiary and tracer. Therefore, an armor-piercing core is found in armor-piercing incendiary and armor-piercing incendiary tracer bullets.

Tracer bullets are designed for target designation, fire correction when firing up to 1000 m. Such bullets are filled with a tracer composition, which is pressed in several steps under very high pressure in order to avoid the destruction of the composition when fired, its burning on a large surface and the destruction of the bullet in flight (and in diagram 122). In the shell of tracer bullets of domestic production, a core made of an alloy of lead with antimony is placed in front, and a glass with a tracer composition pressed into several layers is placed in the back.



Scheme 122. Tracer bullets:

a - bullet T-30 (USSR); b - SPGA bullet (England); in - bullet T (France)

In order to avoid the destruction of the compressed tracer composition in the pool and the disruption of its normal combustion, tracer bullets usually do not knurling (groove) on the side surface for crimping the sleeve mouth into it. Fastening tracer bullets in the muzzle of the sleeve is provided, as a rule, by planting them in the muzzle with an interference fit.

When fired, the flame from the powder charge ignites the tracer composition of the bullet, which, burning in the flight of the bullet, gives a bright luminous trail, clearly visible both day and night. Depending on the time of manufacture and the use of various components in the manufacture of the tracer composition, the glow of the tracer can be green, yellow, orange and crimson.

The most practical is the crimson glow, clearly visible both at night and during the day.

A feature of tracer bullets is the change in weight and the movement of the center of gravity of the bullet as the tracer burns out. A change in weight and a longitudinal shift in the center of gravity do not adversely affect the character of the bullet's flight. But the lateral displacement of the center of gravity, caused by one-sided burnout of the tracer compound, makes the bullet dynamically unbalanced and causes a significant increase in dispersion. In addition, when the tracer burns, chemically aggressive combustion products are released, which have a destructive effect on the bore. When shooting from a machine gun, this does not matter. But the selective and accurate sniper barrel must be protected. Therefore, do not abuse tracer shooting from a sniper rifle. Moreover, the accuracy of firing tracer bullets from the best barrel leaves much to be desired. Moreover, a tracer bullet with weight loss from tracer combustion quickly loses its penetration ability and at a distance of 200 m it no longer even pierces a helmet. Tracer bullet nose painted in green color.

Incendiary bullets were issued before the Second World War and in its initial period. These bullets were intended to destroy flammable targets. In their designs incendiary composition most often placed in the head of the bullet and fired (ignited) when the bullet hit the target (scheme 123). Some incendiary bullets, such as the French one (and in diagram 123), ignited even in the bore from powder gases. The author has seen the shooting of such bullets during forensic shooting. The spectacle was very impressive from the shooter through the range leaving beautiful yellow-orange balls the size of a soccer ball. But there was absolutely no combat effect from this fireworks. Incendiary bullets, which appeared at the end of the First World War to fight enemy plywood and linen airplanes, proved to be untenable against all-metal aircraft. French, Polish, Japanese, Spanish incendiary bullets did not have the necessary penetrating power and were not able to penetrate and set fire even to a railway tank car. The situation was not saved even by the fact that subsequently the incendiary composition was placed inside a strong steel case. The nose of the incendiary bullet is painted red.



Scheme 123. Incendiary bullets:

a - French bullet Ph: 1 - shell, 2 - phosphorus, 3, 4 and 5 - bottom part, 6 - fusible plug; b - Spanish bullet P 1 - core, 2 - point, 3 - heavy body, 4 - incendiary composition (phosphorus); c - German bullet SPr 1 - shell, 2 - incendiary composition (phosphorus), 3 - bottom part; 4 - fusible plug; g - English bullet SA: 1 - shell, 2 - incendiary composition, 3 - bottom part; 4 - fusible plug

Due to low penetration, incendiary bullets quickly began to be forced out of combat use by armor-piercing incendiary bullets, which usually had a tungsten carbide or steel armor-piercing core. The combination of incendiary and armor-piercing action turned out to be very profitable. The designs of armor-piercing incendiary bullets during the Second World War were different in different countries (Scheme 124). Usually, the incendiary composition was still located at the head of the bullet - this way it worked more reliably, but set it on fire worse. Not all the incendiary substance penetrated after the armor-piercing core into the hole formed by it. To avoid this shortcoming, it is more advantageous to place the incendiary composition behind the armor-piercing core, but in this case, the sensitivity of the ignition of the bullet to action against weak obstacles is reduced. The Germans solved this problem in an original way, they placed the incendiary composition around the armor-piercing core (4 in scheme 124, scheme 125).



Scheme 124 Armor-piercing incendiary bullets:

1 - domestic, 2 - Italian; 3 - English; 4 - german



Scheme 125. Armor-piercing incendiary bullet RTK caliber 7.92 (German)

The head part of armor-piercing incendiary bullets is painted black with a red belt.

Armor-piercing incendiary tracer bullets have both armor-piercing, incendiary and tracer effects. They consist of the same elements: a shell, an armor-piercing core, a tracer and an incendiary composition (Scheme 126). The presence of a tracer in these bullets significantly increases their incendiary effect. The nose of the armor-piercing incendiary tracer bullet is painted purple and red.

Scheme 126. Armor-piercing incendiary tracer bullets:

1 - domestic BZT-30;

2 - Italian

Before the Second World War, the so-called sighting and incendiary bullets were used in the armies of some countries (in particular, the USSR and Germany). In theory, they should have given a bright flash at the moment of meeting even with a plywood shield of an ordinary target. These bullets both in the USSR and in Germany had the same design. The principle of their operation was usually based on the fact that the drummer, located on the axis of the bullet and designed to prick the primer, was held in place by mutually closed weights-counterweights in the stowed state. These counterweights when firing and rotating the bullet centrifugal force dispersed to the sides, released or cocked the drummer. When meeting with the target and braking the bullet, the drummer pricked the primer, which ignited the incendiary composition, giving a very bright flash. Once in DOSAAF, where any cartridge "rabble" unnecessary in the army was given for training purposes, the author fired such cartridges of release 1919 (!) in the shoulder. At a distance of 300 m, the flashes from these bullets were visible on a bright sunny day with the naked eye. These bullets, in essence, were explosive, because they really exploded into fragments when they hit the plywood shield. In this case, a hole was formed into which it was possible to stick a fist. According to eyewitnesses, hitting a live target with such bullets had terrible consequences. This ammunition was banned by the Geneva Convention and during the Second World War it was not produced, of course, not for the purposes of humanism, but because of the high cost of production. Old stocks of cartridges with such bullets went into action. Such bullets are unsuitable for sniper shooting due to the large (very large) dispersion. The nose of the sighting-incendiary bullet, just like that of a conventional incendiary bullet, is painted red. These were the very famous explosive bullets that were not advertised either here or in Germany. Their device is shown in diagrams 127, 128.



Scheme 127. Explosive bullets:

a - remote bullet (Germany); b - impact bullet (Germany); c - impact bullet (Spain)



Scheme 128. Explosive bullets of inertial action:

1 - shell; 2 - explosive;

3 - capsule; 4 - fuse; 5 - drummer

The above-described varieties of special bullets are used in all small arms cartridges, not excluding even pistol cartridges, if they are used to fire submachine guns.

Domestic bullets are assigned the following designations: P - pistol; L - ordinary light rifle; PS - ordinary with a steel core; T-30, T-44, T-45, T-46 - tracers; B-32, BZ - armor-piercing incendiary; BZT - armor-piercing incendiary tracer; PZ - sighting and incendiary; 3 - incendiary.

By these markings, you can determine the type of ammunition in the box with cartridges.

At present, the most practically proven light ordinary bullets, tracer and armor-piercing incendiary, have remained in combat use.

In the warehouses of NZ, there are still quite a few large stocks cartridges with all the types of bullets described above, and from time to time these cartridges are supplied both for target practice and for combat use. In galvanized form, combat rifle cartridges can be stored for 70-80 years without losing their fighting qualities.

Small-caliber gross sports and hunting cartridges produced in the USSR could be stored for 4-5 years without changing their fighting qualities. After this period, they began to change the accuracy of the battle in height due to the uneven combustion of gunpowder in different cartridges. After 7-8 years of storage in such cartridges, due to the decomposition of the capsule composition, the number of misfires sharply increased. After 10-12 years of storage, many batches of these cartridges became unusable.

Target small-caliber cartridges, made very high quality and scrupulously, stored in sealed packages and galvanized, did not lose their qualities when stored for 20 years or more. But you should not store small-caliber cartridges for a long time, because they are not designed for long periods of storage.

Cartridges for rifled firearms in all countries of the world are trying to make as high quality as possible. You can't fool classical mechanics. For example, a slight change in the weight of a bullet from the calculated one does not have a significant effect on the accuracy of fire at short distances, but with an increase in the range it makes itself felt quite strongly. With a change in the weight of an ordinary rifle light bullet by 1% (Vini - 865 m / s), the deviation of the trajectory in height at a distance of 500 m will be 0.012 m, at 1200 m - 0.262 m, at 1500 m - 0.75 m.

In sniper practice, a lot depends on the quality of the bullet.

The height of the trajectory of a bullet is affected not only by its weight, but also by the muzzle velocity of the bullet, and the geometry of its streamlining. The initial speed of the bullet, in turn, is affected by the size of the powder charge and the material of the shell: different materials provide different friction of the bullet against the walls of the barrel.

Bullet balance is extremely important. If the center of gravity does not coincide with geometric axis, then the spread of bullets increases, therefore, the accuracy of shooting decreases. This is often observed when firing bullets with various mechanical inhomogeneous fillings.

The smaller the deviations in shape, weight and geometric dimensions in the manufacture of a bullet of a given design, the better the accuracy of shooting, all other things being equal.

In addition, it must be borne in mind that rust on the shell of a bullet, nicks, scratches and other kinds of deformations have a very unfavorable effect on the flight of a bullet in the air and lead to a deterioration in the accuracy of fire.

The maximum pressure of the powder gases ejecting the bullet is influenced by the initial force pressure, which cuts the bullet into the rifling, which in turn depends on how tightly the bullet is pressed into the sleeve and fixed in it by crimping the muzzle for the annular knurling. With different materials of the sleeve, this force will be different. A bullet, obliquely planted in a sleeve, and along the rifling will go in an "oblique" way, in flight it will be unstable and will certainly deviate from the given direction. Therefore, cartridges of old releases must be carefully examined, selected and rejected if errors are found.

The best accuracy of fire is given by ordinary bullets, in which the shell is filled with lead without any other filling. When shooting at a live target, special bullets are not needed.

As you have already seen, rifle ammunition that looks the same and is designed for the same weapon is not the same. For several decades, they were made at different factories, from different materials, under different conditions, with continuously changing requirements of the situation, with bullets of different designs, different weights, different lead fills, different diameters (see Table 38) and different workmanship .

The same-looking cartridges have a different trajectory of a bullet and a different accuracy of battle. When shooting from a machine gun, this does not matter - plus or minus 20 cm above or below. But it is not suitable for sniper shooting. The "rabble" of various cartridges, even the best ones, does not give accurate, heaped and monotonous shooting.

Therefore, the sniper selects exactly for his barrel (barrel to barrel is also different, see below) monotonous cartridges, one series, one factory, one year of manufacture and, even better, from one box. Different batches of cartridges differ from each other in the height of the trajectory. Therefore, for different batches of cartridges sniper weapon need to shoot again.

BULLET PUNCHING

The penetrating effect of a bullet is characterized by the depth of its penetration into an obstacle of a certain density. The live force of a bullet at the moment of its meeting with an obstacle significantly affects the depth of penetration. But besides this, the penetrating effect of a bullet depends on a number of other factors, for example, on the caliber, weight, shape and design of the bullet, as well as on the properties of the medium being penetrated and on the angle of impact. The meeting angle is the angle between the tangent to the trajectory at the meeting point and the tangent to the target (obstacle) surface at the same point. Best result obtained at a meeting angle of 90°. Diagram 129 shows the meeting angle for the case of a vertical barrier.



Scheme 129. Meeting angle

To identify the penetrating effect of a bullet, they use the measurement of its penetration into a package made up of dry pine boards 2.5 cm thick each, with gaps between them for the thickness of the board. When firing at such a package, a light bullet from a sniper rifle pierces: from a distance of 100 m - up to 36 boards, from a distance of 500 m - up to 18 boards, from a distance of 1000 m - up to 8 boards, from a distance of 2000 m - up to 3 boards

The penetrating effect of a bullet depends not only on the properties of the weapon and the bullet, but also on the properties of the barrier being penetrated. A light rifle bullet of the 1908 model pierces at a distance of up to 2000 m:

iron plate 12mm,

Steel plate up to 6 mm,

A layer of gravel or crushed stone up to 12 cm,

A layer of sand or earth up to 70 cm,

Soft clay layer up to 80 cm,

Peat layer up to 2.80 m,

Packed snow layer up to 3.5 m,

Straw layer up to 4 m,

Brick wall up to 15-20 cm,

Oak wood wall up to 70 cm,

Pine wood wall up to 85 cm.

The penetrating effect of a bullet depends on the firing distance and on the angle of impact. For example, an armor-piercing bullet of the 1930 model, when hit along the normal (P90 °), pierces armor 7 mm thick from a distance of 400 m without failure, from a distance of 800 m - less than half, at a distance of 1000 m the armor does not penetrate at all, when the trajectory deviates from the normal by 15 ° from a distance of 400 m, through holes in 7-mm armor are obtained in 60% of cases, and with a deviation from the normal by 30 ° already from a distance of 250 m, the bullet does not penetrate the armor at all.

Armor-piercing bullet of caliber 7.62 mm penetrates:



Penetrating action of a 5.6 mm bullet of a small-caliber side-fire sports cartridge (muzzle velocity 330 m/s, distance 50 m):




Heavy plate body armor from the times of the Great Patriotic War, worn on two padded jackets, holds a light rifle bullet even when fired at close range.

Window pane shatters a rifle bullet. The fact is that the glass particles, acting like emery, when they meet the narrow nose of a rifle bullet, instantly “scrape” the shell from it. The remaining fragments of the bullet fly along a changed unpredictable trajectory and do not guarantee hitting a target that was behind the glass. This phenomenon is observed when shooting from rifles and machine guns with ammunition with pointed bullets. The narrow nose of the bullet at high speed abruptly takes on a large abrasive load and instantly collapses. This phenomenon is not observed in blunt pistol bullets and revolver bullets flying at low subsonic speeds.

Therefore, when shooting at targets located behind glass, it is recommended to shoot either armor-piercing bullets or bullets with a steel core (with a silver nose).

A helmet at a distance of up to 800 m is penetrated by all types of bullets, except for tracers.

With the loss of bullet speed, its penetrating effect decreases (Table 42):

Table 42

7.62mm bullet velocity loss

ATTENTION. Tracer bullets, due to the burnout of the tracer composition, quickly lose mass, and with it their penetrating ability. At a distance of 200 m, the tracer bullet does not even pierce the helmet.

The initial speed of sports small-caliber cartridges with lead bullets of various batches and names ranges from 280-350 m / s. The initial speed of Western small-caliber cartridges with jacketed and semi-shelled bullets of various batches ranges from 380 to 550 m / s.

CARTRIDGES FOR SNIPER SHOOTING

In sniper shooting, two types of cartridges are most preferred, specially designed for use in real combat conditions. The first of them is called "sniper" (photo 195). These cartridges are made with great care, not only with a uniform weight of powder charge and bullets of the same mass, but also with very precise observance of the geometric shape of the bullet, a special soft case material, with a thicker layer of tombac coating. "Sniper" cartridges have a very high accuracy of combat, which is not inferior to the accuracy of combat of special sports-target cartridges of the same caliber with a brass sleeve. The bullet of the "sniper" cartridge is not painted in any way in order to avoid changing the weight balance. These cartridges are specially designed to defeat enemy manpower. Look at the longitudinal section of the bullet of this ammunition (photo 196). There is a void in the head of the bullet, and the hollow nose of the bullet acts as a ballistic fairing tip. It is followed by a steel core and only then - a lead fill. The center of gravity of such a bullet is slightly shifted back. When hitting dense tissues (bone), such a bullet turns sideways, goes somersault, then falls apart into a head (steel) and tail (lead) parts, which move inside the target independently and unpredictably, leaving the enemy no chance of survival. The hunters said that such ammunition was successfully felled even large animal.



Photo 195



Photo 196

1 - empty ballistic tip; 2 - steel core; 3 - lead filling; 4 - bevel of the core; 5 - hollow shank

Thanks to the steel core, the bullets of the "sniper" cartridges have armor penetration 25-30% higher than conventional light bullets. The bullets of this type of ammunition have a streamlined shape of a heavy bullet of the 1930 model, but the weight, equal to weight light bullet, - 9.9 g due to the steel core and the void in the tail. So it was specially conceived by the developers to give the light bullet the useful qualities of a heavy bullet. Therefore, the trajectory of the bullets of the "sniper" cartridges corresponds to Table. 8 exceeding the average trajectories given in this manual and the manual for the SVD rifle.

As already mentioned, the bullets of the "sniper" cartridges are not marked with anything (photo 197). On paper packs of these ammunition there are inscriptions "sniper".



Photo 197

The second type of ammunition, intended for sniper shooting, has a steel-core bullet, the head of which is painted silver (photo 198). They are called so - bullets with a silver nose (bullet weight 9.6 g).



Photo 198

The steel core of this bullet takes up most of its volume (photo 199).



Photo 199

1 - lead fill, 2 - steel core; 3 - lead jacket between steel core and sheath

The head of the bullet has a lead fill for greater stability of the bullet in flight. Such ammunition is designed for sniper work on lightly armored and fortified targets. A bullet with a silver nose marking pierces:




The longitudinal section shows that the core bullets have a streamlined shape of a heavy bullet with a tapered shank. But these bullets are classified as light (weight 9.6 g) because of the steel core, which is lighter than lead of the same volume. The ballistics of these bullets and the accuracy of the battle are almost the same as those of the "sniper" cartridges, and when firing them, one should be guided by the same table of exceeding the average trajectories for the SVD rifle.

The above two types of ammunition were developed in relation to the SVD rifle, but their ballistics practically correspond to Table. 9 excess of average trajectories for a three-line rifle of the 1891-1930 model, given in this manual.

Specialized cartridges of caliber 7.62 mm "sniper" and "silver nose", designed specifically for sniper shooting, are light in weight and transverse load, while having the same perfect aerodynamic shape as the heavy bullets of the 1930 model, so their trajectory at a distance of up to 500 m it corresponds to the trajectory of a light bullet, and at a distance of 500 to 1300 m it corresponds to the trajectory of a heavy bullet. Therefore, in the table of excess of average trajectories for SVD rifles ballistic data are indicated for firing a light bullet, namely: "sniper", "silver nose" cartridges and bulk machine-gun and rifle cartridges with a steel core.

Bullets of "sniper" cartridges are made light for increased action on a live target. The speed of a light bullet is faster than a heavy one. As is already known, a bullet hitting a live target at a speed of 700 m/s or more causes water hammer and the associated physiological shock, instantly incapacitating the target. Such an effect of a light bullet of a sniper cartridge on a target remains practically up to 400-500 m, after this distance the speed of the bullet is reduced by air resistance, but the damaging effect of the bullet of the "sniper" cartridge does not decrease at all. Why? Take a close look at the longitudinal cut of this bullet. the steel core in the head part has a slightly noticeable bevel with the right side up (see photo 196). This creates, albeit insignificant, but a preponderance of mass on one side of the bullet head. As it rotates, this counterweight pushes the bullet's nose more and more to the side, and it becomes more and more unstable horizontally. Therefore, the farther the distance to the target, the more unstable the bullet becomes when approaching it. At firing distances further than 400-500 m, a sniper cartridge bullet, even when it hits soft tissues, turns sideways and, if it does not fall apart, begins to tumble, leaving minced meat behind.

With all this, the bullet of the "sniper" cartridge holds up very well in the wind (as they say, "stands into the wind") and is guaranteed to maintain a stable position in flight at a firing distance of 200 m.

Accuracy of combat cartridges "sniper" can be considered absolute. All the failures that occur when working with these cartridges can only be explained by the reduced quality of the barrel or the mistakes of the shooter. The unique ballistic data of the above-described ammunition and its increased effect on the target caused noticeable confusion among the NATO military during the recent Balkan conflicts.

AMMUNITION SELECTION

In real combat practice, it is not always necessary to shoot ammunition made and intended specifically for sniper shooting. Sometimes you have to shoot with what is available. Galvanized bulk cartridges made in the pre-war, war and post-war times (1936-1956) often have an incorrect "oblique" bullet fit in the case muzzle. These are the so-called "crooked" cartridges, in which the bullet is slightly deflected to the side from the common axis of the cartridge case - the bullet. Such a "curve" bullet landing is noticeable to the eye. Even the non-uniformity of the bullet's seat in the case in depth is noticeable to the eye: very often the bullets are planted either too deep or protrude excessively.

Bullets with an "oblique" landing will also go along the barrel in an "oblique" way, and therefore they will not provide shooting accuracy. Bullets with unequal fits will give unequal barrel pressure and indicate vertical spread. By visual inspection, such cartridges are rejected and given to machine gunners. Of course, gross cartridges with light bullets of the 1908-1930 model. will have a much wider spread than sniper or sports targets, but in war it's better than nothing.

You can shoot any cartridges that are new in appearance, do not have strong abrasions, scratches, dents, rust on the surface.

Cartridges with scuffs indicate that they were dragged through pockets and pouches for a very long time and it is not known under what circumstances. This ammo may be wet, in which case it may not work.

Do not use cartridges that have even slight dents on the sleeves. It's not that such ammunition does not go into the chamber; if necessary, they can be driven there by force. The fact is that a dent that straightens under diabolical pressure hits the wall of the chamber with great force and can simply break it. There have been such cases. You can not use cartridges with rusty shells and rusty bullets. A rusty bullet shell can fall apart and fragments of a deformed bullet will fly in unpredictable directions. A rusty sleeve can simply be torn apart. In this case, it happens that the remnants of the sleeve do not just burn to the chamber, but are tightly welded to it. It happens that in this case, when gases break through back, the valve is welded to receiver and, in addition, the shooter receives a strong gas blow to the face with the risk of eye damage.

You can not use cartridges produced in the first half of the 30s and earlier. Such ammunition often detonates; it happens that at the same time the barrel blows to shreds, tearing off the arrow with the fingers of the left hand.

You can not carry cartridges in leather pouches and bandoliers - only in canvas or tarpaulin. From contact with the skin, the metal of clad ammunition is covered with a green coating and rust.

And, of course, you can’t lubricate the ammunition - after that they don’t shoot. Due to the force of surface tension, even the thickest lubricant sooner or later penetrates inside the cartridge and envelops the primer and powder charges, which then do not work. To protect cartridges from moisture, they are allowed to be lubricated with a thin layer. lard, and such ammunition is recommended to be used in the first place and quickly.

Do not forget that tracer bullets damage the barrel and at a distance of 200 m (and even less) do not even pierce the helmet. Use tracer bullets when absolutely necessary and for target designation.

If possible, calibrate bulk cartridges according to the diameter of the bullet and select for firing cartridges with bullets of the same diameter and depth in the case. Snipers of the old formation gross cartridges (and even target ones) must weigh and reject those that have deviations in the total weight. If possible, you should do the same. With all this, you will dramatically increase the accuracy of the battle of your trunk.

Always have a few pieces of armor-piercing incendiary and tracer cartridges. Combat necessity may require their use under the most unexpected circumstances.

Do not use cartridges in which the primer protrudes from the bottom of the case. When closing the shutter, such a cartridge may fire prematurely.

Do not use cartridges with corroded or cracked primers. Such a primer can pierce with a drummer.

If a misfire occurs and this cartridge is not your last, throw it away without regret. You cannot "click" on this cartridge a second time. A strong rifle striker can pierce the primer, and the gas stream in this case hits the shooter in the face with the power of an ungloved boxing fist. Once upon a time, in his youth, the author did not believe in this until he received such a terrible gas slap in the face. The feeling was as if the head had been torn off and everything else existed on its own.

Very rarely, but still, a very dangerous phenomenon occurs, called a protracted shot. It happens that lumped or damp gunpowder does not ignite immediately, but after some time. Therefore, in the event of a misfire, never rush to immediately open the shutter. After a misfire, count to ten, and if the shot does not occur, open the bolt abruptly and throw out the unfired cartridge. The author witnessed a case when a young cadet, unable to withstand the 5-6 seconds required after a misfire, pulled the bolt towards himself, the cartridge flew out, fell under the instructor's feet and exploded. No harm done. But if this cartridge worked at the moment the shutter was opened, the consequences would be terrible.

These breathtaking photographs capture the moment a bullet exits a barrel at over 365 meters per second. The author of the project was the Finnish photographer Herra Kuulapaa, who has been perfecting the unusual high-speed shooting technique for the last 7 years. In addition to the beautiful visual effect, his work has a scientific background.

(Total 20 photos)

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1. Seven years ago, a group of amateur photographers launched an initiative that later grew into a project that helps firearms manufacturers better understand the fire processes that occur at the moment of a shot. This allows companies to improve their products Pictured is a modified Austrian Glock.



2. “Sports shooting enthusiasts around the world are eager to find out what happens in milliseconds at the moment a bullet leaves the bore. Our new method allowed us to obtain detailed 3D images of a projectile fired from a firearm. You can see 3D images of the explosion and the powder gas flow,” says Kuulapaa.



3. In the photo: Bullets fly at a speed of 1,280 km / h



4. None of the moments depicted in the pictures can be seen with the naked eye, since the action takes place in hundredths of a second. But these are not just beautiful photos, they provide weapons manufacturers with information about the flow of gases and the distribution of temperature during a shot to improve their products.



5. The bullet leaves the barrel of the weapon when fired in milliseconds.



6. Many frames show an impressive flash when fired.



7. The photographer admits that he often accidentally damages his equipment and lenses, trying to capture the right moment.



8. Shot from the Smith & Wesson Model 500 (Smith & Wesson Model 500), the most powerful mass-produced revolver to date



9. The mass of the giant of the sky of cartridges is 2 kg 60 g. Smith and Wesson model 500 in the movie "Return of the Hero" with Schwarzenegger



10. In the collage: A sequence of shots showing a bullet fired from a rifle.



11. Shot with our 7.62x39mm cartridge from an American AR-15 rifle. It is considered the third most powerful automatic cartridge in the world.



12. "Our latest achievement is 3D shooting of a shot, where you can see a three-dimensional picture."



13. A cloud of gases when fired



14. The initial moment of a shot from an AR-15 rifle



15. A bullet flies out at a speed of 3,050 km / h, which is much faster than when fired from a pistol.