Marry

Armor-piercing projectile 125 mm. Anti-tank projectiles and their varieties. Anti-tank guided missiles

) and 40 tons ("Puma", "Namer"). In this regard, overcoming the armor protection of these vehicles is a serious problem for anti-tank ammunition, which includes armor-piercing and cumulative projectiles, rockets and rocket-propelled grenades with kinetic and cumulative warheads, as well as striking elements with an impact core.

Among them, armor-piercing sub-caliber shells and missiles with a kinetic warhead are the most effective. Possessing high armor penetration, they differ from other anti-tank munitions in their high approach speed, low sensitivity to the effects of dynamic protection, the relative independence of the weapon guidance system from natural / artificial interference, and low cost. Moreover, these types of anti-tank ammunition can be guaranteed to overcome the active protection system of armored vehicles, all in more gaining ground as a frontier for the interception of submunitions.

Currently, only armor-piercing sub-caliber shells have been adopted for service. They are fired mainly from smooth-bore guns of small (30-57 mm), medium (76-125 mm) and large (140-152 mm) calibers. The projectile consists of a two-bearing leading device, the diameter of which coincides with the diameter of the barrel bore, consisting of sections separated after departure from the barrel, and a striking element - an armor-piercing rod, in the bow of which a ballistic tip is installed, in the tail - an aerodynamic stabilizer and a tracer charge.

As the material of the armor-piercing rod, ceramics based on tungsten carbide (density 15.77 g / cc), as well as metal alloys based on uranium (density 19.04 g / cc) or tungsten (density 19.1 g / cc) are used. cc). The diameter of the armor-piercing rod ranges from 30 mm (obsolete models) to 20 mm (modern models). The higher the density of the rod material and the smaller the diameter, the greater the specific pressure exerted by the projectile on the armor at the point of its contact with the front end of the rod.

Metal rods have much greater bending strength than ceramic ones, which is very important when the projectile interacts with active protection shrapnel elements or explosive dynamic protection plates. At the same time, the uranium alloy, despite its somewhat lower density, has an advantage over tungsten - the armor penetration of the first is 15-20 percent greater due to the ablative self-sharpening of the rod in the process of penetrating armor, starting from an impact speed of 1600 m / s, provided by modern cannon shots.

The tungsten alloy begins to exhibit ablative self-sharpening starting at 2000 m/s, requiring new ways to accelerate projectiles. At a lower speed, the front end of the rod flattens out, increasing the penetration channel and reducing the penetration depth of the rod into the armor.

Along with the indicated advantage, the uranium alloy has one drawback - in the case of nuclear conflict neutron radiation penetrating the tank induces secondary radiation in the uranium, which affects the crew. Therefore, in the arsenal armor-piercing shells it is necessary to have models with rods made of both uranium and tungsten alloys, designed for two types of military operations.

Uranium and tungsten alloys also have pyrophoricity - the ignition of heated metal dust particles in air after breaking through the armor, which serves as an additional damaging factor. The specified property manifests itself in them, starting from the same speeds as the ablative self-sharpening. Dust is another damaging factor. heavy metals, which has a negative biological effect on the crew of enemy tanks.

The leading device is made of aluminum alloy or carbon fiber, the ballistic tip and aerodynamic stabilizer are made of steel. The lead device serves to accelerate the projectile in the bore, after which it is discarded, so its weight must be minimized by using composite materials instead of aluminum alloy. The aerodynamic stabilizer is subjected to thermal effects from the powder gases generated during the combustion of the powder charge, which can affect the accuracy of shooting, and therefore it is made of heat-resistant steel.

The armor penetration of kinetic projectiles and missiles is defined as the thickness of a homogeneous steel plate, set perpendicular to the axis of the projectile's flight, or at a certain angle. In the latter case, the reduced penetration of the equivalent thickness of the plate is ahead of the penetration of the plate, installed along the normal, due to the large specific loads at the entrance and exit of the armor-piercing rod into / out of the inclined armor.

Upon entering the sloping armor, the projectile forms a characteristic roller above the penetration channel. The blades of the aerodynamic stabilizer, collapsing, leave a characteristic "star" on the armor, by the number of rays of which it is possible to determine the belonging of the projectile (Russian - five rays). In the process of breaking through the armor, the rod is intensively ground off and significantly reduces its length. When leaving the armor, it elastically bends and changes the direction of its movement.

A characteristic representative of the penultimate generation of armor-piercing artillery ammunition is the Russian 125-mm separate-loading round 3BM19, which includes a 4Zh63 cartridge case with the main propellant charge and a 3BM44M cartridge case containing an additional propellant charge and actually sub-caliber projectile 3BM42M "Lekalo". Designed for use in the 2A46M1 gun and newer modifications. The dimensions of the shot allow it to be placed only in modified versions of the automatic loader.

The ceramic core of the projectile is made of tungsten carbide, placed in a steel protective case. The leading device is made of carbon fiber. As the material of the sleeves (except for the steel pallet of the main propellant charge), cardboard impregnated with trinitrotoluene was used. The length of the cartridge case with the projectile is 740 mm, the length of the projectile is 730 mm, the length of the armor-piercing rod is 570 mm, and the diameter is 22 mm. The weight of the shot is 20.3 kg, the cartridge case with the projectile is 10.7 kg, the armor-piercing rod is 4.75 kg. The initial speed of the projectile is 1750 m / s, armor penetration at a distance of 2000 meters along the normal is 650 mm of homogeneous steel.

The latest generation of Russian armor-piercing artillery ammunition is represented by 125-mm separate-loading rounds 3VBM22 and 3VBM23, equipped with two types of sub-caliber projectiles - respectively 3VBM59 "Lead-1" with an armor-piercing rod made of tungsten alloy and 3VBM60 with an armor-piercing rod made of uranium alloy. The main propellant charge is loaded into the 4Zh96 "Ozon-T" cartridge case.

The dimensions of the new projectiles coincide with the dimensions of the Lekalo projectile. Their weight is increased to 5 kg due to the greater density of the rod material. To disperse heavy shells in the barrel, a more voluminous main propellant charge is used, which limits the use of shots, including Lead-1 and Lead-2 shells, only to the new 2A82 gun, which has an enlarged charging chamber. Armor penetration at a distance of 2000 meters along the normal can be estimated as 700 and 800 mm of homogeneous steel, respectively.

Unfortunately, the Lekalo, Lead-1 and Lead-2 projectiles have a significant design flaw in the form of centering screws located along the perimeter of the supporting surfaces of the leading devices (protrusions visible in the figure on the front supporting surface and points on the surface of the sleeve ). Centering screws are used for stable management projectile in the bore, but their heads at the same time have a destructive effect on the surface of the channel.

In foreign designs of the latest generation, precision obturator rings are used instead of screws, which reduces barrel wear by a factor of five when fired with an armor-piercing sub-caliber projectile.

The previous generation of foreign armor-piercing sub-caliber projectiles is represented by the German DM63, which is part of a unitary shot for the standard 120 mm NATO smoothbore gun. Armor-piercing rod is made of tungsten alloy. The weight of the shot is 21.4 kg, the weight of the projectile is 8.35 kg, the weight of the armor-piercing rod is 5 kg. Shot length is 982 mm, projectile length is 745 mm, core length is 570 mm, diameter is 22 mm. When firing from a cannon with a barrel length of 55 calibers, the initial speed is 1730 m / s, the speed drop on the flight path is declared at the level of 55 m / s for every 1000 meters. Armor penetration at a distance of 2000 meters normal is estimated at 700 mm of homogeneous steel.

The latest generation of foreign armor-piercing sub-caliber projectiles includes the American M829A3, which is also part of the unitary shot for the standard 120-mm NATO smoothbore gun. Unlike the D63 projectile, the armor-piercing rod of the M829A3 projectile is made of a uranium alloy. The weight of the shot is 22.3 kg, the weight of the projectile is 10 kg, the weight of the armor-piercing rod is 6 kg. Shot length is 982 mm, projectile length is 924 mm, core length is 800 mm. When firing from a cannon with a barrel length of 55 calibers, the initial speed is 1640 m/s, the speed drop is declared at the level of 59.5 m/s for every 1000 meters. Armor penetration at a distance of 2000 meters is estimated at 850 mm homogeneous steel.

When comparing the latest generation of Russian and American sub-caliber projectiles equipped with armor-piercing uranium alloy cores, a difference in the level of armor penetration is visible, to a greater extent due to the degree of elongation of their striking elements - 26-fold for the lead of the Lead-2 projectile and 37-fold for the rod projectile М829А3. In the latter case, a quarter greater specific load is provided at the point of contact between the rod and armor. In general, the dependence of the armor penetration value of shells on the speed, weight and elongation of their striking elements is shown in the following diagram.

An obstacle to increasing the elongation of the striking element and, consequently, the armor penetration of Russian projectiles is the automatic loader device, first implemented in 1964 in the Soviet T-64 tank and repeated in all subsequent models. domestic tanks, which provides for the horizontal arrangement of projectiles in the conveyor, the diameter of which cannot exceed the internal width of the hull, equal to two meters. Taking into account the case diameter of Russian shells, their length is limited to 740 mm, which is 182 mm less than the length of American shells.

In order to achieve parity with the cannon weapons of a potential enemy for our tank building, the priority for the future is the transition to unitary shots, located vertically in an automatic loader, the shells of which have a length of at least 924 mm.

Other ways to increase the effectiveness of traditional armor-piercing projectiles without increasing the caliber of guns have practically exhausted themselves due to restrictions on the pressure in the barrel chamber developed during the combustion of a powder charge, due to the strength of weapon steel. When moving to a larger caliber, the size of the shots becomes comparable to the width of the tank hull, forcing the shells to be placed in the aft niche of the turret with increased dimensions and a low degree of protection. For comparison, the photo shows a shot of 140 mm caliber and a length of 1485 mm next to a mock shot of a 120 mm caliber and a length of 982 mm.

In this regard, in the United States, within the framework of the MRM (Mid Range Munition) program, active missiles MRM-KE with kinetic warhead and MRM-CE with HEAT warhead. They are loaded into the cartridge case of a standard 120-mm cannon shot with a propellant charge of gunpowder. The caliber body of the shells contains a radar homing head (GOS), a striking element (an armor-piercing rod or a shaped charge), impulse trajectory correction engines, an accelerating rocket engine and a tail unit. The weight of one projectile is 18 kg, the weight of the armor-piercing rod is 3.7 kg. The initial speed at the level of the muzzle is 1100 m/s, after the completion of the accelerating engine, it increases to 1650 m/s.

Even more impressive performance has been achieved in the framework of the creation of the CKEM (Compact Kinetic Energy Missile) anti-tank kinetic missile, the length of which is 1500 mm, weight 45 kg. The rocket is launched from a transport and launch container using a powder charge, after which the rocket is accelerated by an accelerating solid-propellant engine to a speed of almost 2000 m / s (Mach 6.5) in 0.5 seconds.

The subsequent ballistic flight of the rocket is carried out under the control of the radar seeker and aerodynamic rudders with stabilization in the air using the tail unit. The minimum effective firing range is 400 meters. The kinetic energy of the damaging element - armor-piercing rod at the end of jet acceleration reaches 10 mJ.

During the tests of the MRM-KE projectiles and the CKEM rocket, the main drawback of their design was revealed - unlike sub-caliber armor-piercing projectiles with a separating leading device, the inertia flight of the striking elements of a caliber projectile and a kinetic missile is carried out assembled with a body of large cross-section and increased aerodynamic resistance, which causes a significant drop in speed on the trajectory and a decrease in the effective firing range. In addition, the radar seeker, impulse correction engines and aerodynamic rudders have a low weight perfection, which makes it necessary to reduce the weight of the armor-piercing rod, which negatively affects its penetration.

The way out of this situation is seen in the transition to the separation in flight of the caliber body of the projectile / rocket and the armor-piercing rod after the completion of the rocket engine, by analogy with the separation of the leading device and the armor-piercing rod, which are part of the sub-caliber projectiles, after their departure from the barrel. Separation can be carried out with the help of an expelling powder charge, which is triggered at the end of the accelerating section of the flight. Reduced-size seeker should be located directly in the ballistic tip of the rod, while the flight vector control must be implemented on new principles.

A similar technical problem was solved as part of the BLAM (Barrel Launched Adaptive Munition) project to create small-caliber guided artillery shells, performed at the Adaptive Aerostructures Laboratory AAL (Adaptive Aerostructures Laboratory) of Auburn University by order of the US Air Force. The aim of the project was to create a compact homing system that combines a target detector, a controlled aerodynamic surface and its drive in one volume.

The developers decided to change the direction of flight by deflecting the projectile tip at a small angle. At supersonic speed, a fraction of a degree deflection is enough to create a force capable of implementing a control action. A simple technical solution was proposed - the ballistic tip of the projectile rests on a spherical surface, which plays the role of a ball bearing, several piezoceramic rods are used to drive the tip, arranged in a circle at an angle to the longitudinal axis. Changing their length depending on the applied voltage, the rods deflect the tip of the projectile to the desired angle and with the desired frequency.

The calculations determined the strength requirements for the control system:
- accelerating acceleration up to 20,000 g;
- acceleration on the trajectory up to 5,000 g;
- projectile speed up to 5000 m / s;
— tip deflection angle up to 0.12 degrees;
— drive actuation frequency up to 200 Hz;
- drive power 0.028 watts.

Recent advances in the miniaturization of infrared sensors, laser accelerometers, computing processors and lithium-ion power supplies resistant to high accelerations (such as electronic devices for guided projectiles - American and Russian), make it possible in the period up to 2020 to create and adopt kinetic projectiles and missiles with an initial flight speed of more than two kilometers per second, which will significantly increase the effectiveness of anti-tank munitions, and also make it possible to abandon the use of uranium as part of their striking elements.

The term "sub-caliber projectile" is most often used in tank forces. Such shells are used along with cumulative and high-explosive fragmentation. But if earlier there was a division into armor-piercing and sub-caliber ammunition, now it makes sense to talk only about armor-piercing sub-caliber projectiles. Let's talk about what a subcaliber is and what are its key features and principle of operation.

basic information

The key difference between sub-caliber shells and conventional armored shells is that the diameter of the core, that is, the main part, is less than the caliber of the gun. At the same time, the second main part - the pallet - is made according to the diameter of the gun. The main purpose of such ammunition is to defeat heavily armored targets. Usually this heavy tanks and fortified buildings.

It is worth noting that the armor-piercing sub-caliber projectile has increased penetration due to the high initial flight speed. Also increased the specific pressure when breaking through the armor. To do this, it is desirable to use materials having the highest possible specific gravity as the core. For these purposes, tungsten and depleted uranium are suitable. Stabilization of the flight of the projectile is implemented by plumage. There is nothing new here, since the principle of the flight of an ordinary arrow is used.

Armor-piercing sub-caliber projectile and its description

As we noted above, such ammunition is ideal for firing at tanks. It is interesting that the subcaliber does not have the usual fuse and explosive. The principle of operation of the projectile is completely based on its kinetic energy. In comparison, it is something like a massive high-velocity bullet.

The subcaliber consists of a coil body. A core is inserted into it, which is often made 3 times smaller than the caliber of the gun. High-strength metal-ceramic alloys are used as the core material. If earlier it was tungsten, today depleted uranium is more popular for a number of reasons. During the shot, the pallet takes over the entire load, thereby ensuring the initial flight speed. Since the weight of such a projectile is less than a conventional armor-piercing one, by reducing the caliber, it was possible to increase the flight speed. These are significant values. So, a feathered sub-caliber projectile flies at a speed of 1,600 m/s, while a classic armor-piercing projectile flies at 800-1,000 m/s.

The action of a sub-caliber projectile

Quite interesting is how such ammunition works. During contact with the armor, it creates a small diameter hole in it due to high kinetic energy. Part of the energy is spent on the destruction of the target's armor, and the projectile fragments fly into the armored space. Moreover, the trajectory is similar to a divergent cone. This leads to the fact that the mechanisms and equipment of the equipment fail, the crew is affected. Most importantly, due to the high degree of pyrophoricity of depleted uranium, numerous fires occur, which in most cases leads to the complete failure of the combat unit. We can say that the sub-caliber projectile, the principle of which we have considered, has increased armor penetration at long distances. Evidence of this is Operation Desert Storm, when the US Armed Forces used sub-caliber ammunition and hit armored targets at a distance of 3 km.

Varieties of PB shells

Currently, several effective designs of sub-caliber projectiles have been developed, which are used by the armed forces of various countries. In particular, we are talking about the following:

With non-separable tray. The projectile passes all the way to the target as a single whole. Only the core is involved in the penetration. This solution has not received sufficient distribution due to increased aerodynamic drag. As a result, the armor penetration rate and accuracy drop significantly with the distance to the target.
With non-detachable tray for conical implements. The essence of this solution is that when passing through the conical shaft, the pallet is crushed. This allows you to reduce aerodynamic drag.
Sub-caliber projectile with detachable pallet. The bottom line is that the pallet is torn off by air forces or by centrifugal forces (with a rifled gun). This allows you to significantly reduce air resistance in flight.

About cumulatives

For the first time, such ammunition was used by Nazi Germany in 1941. At that time, the USSR did not expect the use of such shells, since their principle of operation, although known, was not yet in service. Key Feature similar projectiles was that they had high armor penetration due to the presence of instantaneous fuses and a cumulative recess. The problem, which was encountered for the first time, was that the projectile rotated during the flight. This led to the dispersion of the cumulative arrow and, as a result, reduced armor penetration. In order to exclude negative effect, it was proposed to use smoothbore guns.

Some interesting facts

It is worth noting that it was in the USSR that arrow-shaped armor-piercing sub-caliber shells were developed. This was a real breakthrough, as it was possible to increase the length of the core. Almost no armor protected from a direct hit of such ammunition. Only a successful angle of inclination of the armor plate and, consequently, its increased thickness in the reduced state could help out. In the end, BOPS had such an advantage as a flat flight path at a distance of up to 4 km and high accuracy.

Conclusion

A cumulative sub-caliber projectile is somewhat similar to a conventional sub-caliber. But in its body it has a fuse and an explosive. When breaking through the armor, such ammunition provides destructive action both equipment and manpower. Currently, the most common shells for cannons with a caliber of 115, 120, 125 mm, as well as artillery pieces of 90, 100 and 105 mm. In general, this is all the information on this topic.

This article will cover Various types ammunition and their armor penetration. Photographs and illustrations of traces of armor remaining after a projectile hit are given, as well as an analysis of the overall effectiveness of various types of ammunition used to destroy tanks and other armored vehicles.
When studying this issue, it should be noted that armor penetration depends not only on the type of projectile, but also on the combination of many other factors: firing range, muzzle velocity, type of armor, armor slope angle, etc. mm armor plates of various types. The shelling was carried out with 75-mm armor-piercing shells in order to show the difference in the resistance of armor of the same thickness, but of different types.

The iron armor plate had a brittle fracture of the rear surface, with numerous spalls in the area of the hole. The impact speed is chosen in such a way that the projectile is stuck in the plate. Penetration is nearly achieved with a projectile speed of just 390.3 m/s. The projectile itself was not damaged at all, and will certainly work properly, breaking through such armor.

Iron-nickel armor, without hardening according to the Krupp method (that is, in fact - structural steel) - demonstrated plastic failure with a classic "envelope" (cross-shaped tear on the rear surface), without any traces of fragmentation. As you can see, close to the previous test, the projectile impact speed no longer even leads to through penetration (hit No. I). And only an increase in speed to 437 m / s leads to a violation of the integrity of the rear surface of the armor (the projectile did not penetrate the armor, but a through hole was formed). To achieve a result similar to the first test, it is necessary to bring the speed of the projectile to the armor up to 469.2 m/s (it would not be superfluous to recall that the kinetic energy of the projectile grows in proportion to the square of the speed, i.e. almost one and a half times!). At the same time, the projectile was destroyed, its charging chamber was opened - it will no longer be able to work properly.

Krupp armor - the high hardness front layer contributed to the splitting of shells, while the softer base of the armor deformed, absorbing the energy of the projectile. The first three shells collapsed almost without even leaving marks on the armor plate. Projectile No. IV, which hit the armor at a speed of 624 m / s, also completely collapsed, but this time almost squeezing out the “cork” in its caliber. We can assume that with a further, even a slight increase in the speed of the meeting, a through penetration will occur. But to overcome the Krupp armor, the projectile had to be given more than 2.5 times more kinetic energy!

Armor-piercing projectile

The most massive type of ammunition used against tanks. And as the name implies, it was created specifically for breaking through armor. According to their design, armor-piercing shells were solid blanks (without an explosive charge in the body) or shells with a chamber (inside which an explosive charge was placed). Blanks were easier to manufacture and hit the crew and mechanisms of an enemy tank only at the point of penetration of the armor. Chamber shells were more difficult to manufacture, but when armor was pierced, explosives exploded in the chamber, causing more damage to the crew and mechanisms of an enemy tank, increasing the likelihood of detonation of ammunition or arson of fuel and lubricants.

Also, the shells were sharp-headed and blunt-headed. Equipped with ballistic tips to give the correct angle when meeting with sloped armor and reduce ricochet.

HEAT projectile

Cumulative projectile. The principle of operation of this armor-piercing ammunition is significantly different from the principle of operation of kinetic ammunition, which includes conventional armor-piercing and sub-caliber projectiles. A cumulative projectile is a thin-walled steel projectile filled with a powerful explosive - RDX, or a mixture of TNT and RDX. At the front of the projectile, explosives have a goblet-shaped recess lined with metal (usually copper). The projectile has a sensitive head fuse. When a projectile collides with armor, an explosive is detonated. At the same time, the lining metal is melted and compressed by an explosion into a thin jet (pestle), flying forward at an extremely high speed and penetrating armor. Armored action is provided by a cumulative jet and splashes of armor metal. The hole of the HEAT projectile is small and has melted edges, which has led to a common misconception that HEAT projectiles “burn through” the armor. The penetration of a HEAT projectile does not depend on the velocity of the projectile and is the same at all distances. Its production is quite simple, the production of the projectile does not require the use a large number scarce metals. The cumulative projectile can be used against infantry and artillery as a high-explosive fragmentation projectile. At the same time, cumulative shells during the war years were characterized by numerous shortcomings. The manufacturing technology of these projectiles was not sufficiently developed, as a result, their penetration was relatively low (approximately corresponded to the caliber of the projectile or slightly higher) and was characterized by instability. The rotation of the projectile at high initial speeds made it difficult for the formation of a cumulative jet, as a result, the cumulative projectiles had a low initial velocity, a small effective range shooting and high dispersion, which was also facilitated by the non-optimal form of the projectile head from the point of view of aerodynamics (its configuration was determined by the presence of a notch). The big problem was the creation of a complex fuse, which should be sensitive enough to quickly undermine the projectile, but stable enough not to explode in the barrel (the USSR was able to work out such a fuse suitable for use in powerful tank and anti-tank guns, only at the end of 1944). The minimum caliber of a cumulative projectile was 75 mm, and the effectiveness of cumulative projectiles of this caliber was greatly reduced. Mass production of HEAT shells required the deployment of large-scale production of hexogen. The most massive HEAT shells were used by the German army (for the first time in the summer-autumn of 1941), mainly from 75 mm caliber guns and howitzers. The Soviet army used cumulative shells, created on the basis of captured German ones, from 1942-43, including them in the ammunition of regimental guns and howitzers that had a low muzzle velocity. The British and American armies used shells of this type, mainly in heavy howitzer ammunition. Thus, in the Second World War (unlike the present, when improved shells of this type form the basis of the ammunition load of tank guns), the use of cumulative shells was rather limited, mainly they were considered as a means of anti-tank self-defense of guns that had low initial speeds and low armor penetration by traditional shells (regimental guns, howitzers). At the same time, all participants in the war actively used other anti-tank weapons with cumulative ammunition - grenade launchers (illustration No. 8), aerial bombs, hand grenades.

Sub-caliber projectile

Sub-caliber projectile. This projectile had enough complex structure, which consisted of two main parts - an armor-piercing core and a pallet. The task of the pallet, made of mild steel, was to disperse the projectile in the bore. When the projectile hit the target, the pallet was crushed, and the heavy and hard sharp-headed core made of tungsten carbide pierced the armor. The projectile did not have a bursting charge, ensuring that the target was hit by fragments of the core and fragments of armor heated to high temperatures. Sub-caliber shells had a significantly lower weight compared to conventional armor-piercing shells, which allowed them to accelerate in the gun barrel to significantly higher speeds. As a result, the penetration of sub-caliber shells turned out to be significantly higher. The use of sub-caliber shells made it possible to significantly increase the armor penetration of the existing guns, which made it possible to hit more modern, well-armored armored vehicles even with outdated guns. At the same time, sub-caliber shells had a number of disadvantages. Their shape resembled a coil (there were shells of this type and a streamlined shape, but they were much less common), which greatly worsened the ballistics of the projectile, in addition, a light projectile quickly lost speed; as a result, at long distances, the armor penetration of sub-caliber shells dropped dramatically, turning out to be even lower than that of classic armor-piercing shells. Sub-caliber shells did not work well on sloped armor, because under the action of bending loads the hard but brittle core easily broke. The armored effect of such shells was inferior to armor-piercing caliber shells. Sub-caliber projectiles of small caliber were ineffective against armored vehicles that had protective shields made of thin steel. These shells were expensive and difficult to manufacture, and most importantly, scarce tungsten was used in their manufacture. As a result, the number of sub-caliber shells in the ammunition load of guns during the war years was small, they were allowed to be used only to destroy heavily armored targets at short distances. The German army was the first to use sub-caliber shells in small quantities in 1940 during the fighting in France. In 1941, faced with heavily armored Soviet tanks, the Germans switched to the widespread use of sub-caliber shells, which significantly increased the anti-tank capabilities of their artillery and tanks. However, the shortage of tungsten limited the release of shells of this type; as a result, in 1944, the production of German sub-caliber shells was discontinued, while most of the shells fired during the war years had a small caliber (37-50 mm). Trying to get around the problem of tungsten, the Germans produced Pzgr.40(C) sub-caliber projectiles with a steel core and Pzgr.40(W) surrogate projectiles, which were a sub-caliber projectile without a core. In the USSR, a fairly mass production of sub-caliber shells, created on the basis of captured German ones, began at the beginning of 1943, and most of the shells produced were of 45 mm caliber. The production of these shells of larger calibers was limited by the shortage of tungsten, and they were issued to the troops only when there was a threat of an enemy tank attack, and a report was required for each spent shell. Also, sub-caliber shells were used to a limited extent by the British and American armies in the second half of the war.

high-explosive projectile

High-explosive fragmentation projectile. It is a thin-walled steel or steel-cast iron projectile filled with an explosive (usually TNT or ammonite), with a head fuse. Unlike armor-piercing shells, high-explosive shells did not have a tracer. Upon hitting the target, the projectile explodes, hitting the target with fragments and a blast wave, either immediately - a fragmentation action, or with some delay (which allows the projectile to go deeper into the ground) - a high-explosive action. The projectile is intended mainly to destroy openly located and covered infantry, artillery, field shelters (trenches, wood-and-earth firing points), unarmored and lightly armored vehicles. Well-armored tanks and self-propelled guns are resistant to high-explosive fragmentation shells. However, projectile impact large caliber can cause the destruction of lightly armored vehicles, and damage to heavily armored tanks, consisting in cracking of armor plates (illustration No. 19), jamming of the turret, failure of instruments and mechanisms, injuries and shell shock to the crew.

Literature / useful materials and links:

Artillery (State Military Publishing House of the People's Commissariat of Defense of the USSR. Moscow, 1938)
Artillery Sergeant's Manual ()
Artillery book. Military publishing house of the Ministry of Defense of the USSR. Moscow - 1953 ()
Internet materials

What affects tanks besides grenade launchers and anti-tank systems? How does armor-piercing ammunition work? In this article, we will talk about armor-piercing ammunition. The article, which will be of interest to both dummies and those who understand the topic, was prepared by our team member Eldar Akhundov, who once again pleases us with interesting reviews on the topic of weapons.

Story

Armor-piercing shells are designed to hit targets protected by armor, as their name implies. They first began to be widely used in naval battles in the second half of the 19th century with the advent of ships protected by metal armor. The effect of simple high-explosive fragmentation projectiles on armored targets was not enough due to the fact that during the explosion of the projectile, the energy of the explosion is not concentrated in any one direction, but is dissipated into the surrounding space. Only part shock wave affects the armor of the object trying to break through / bend it. As a result, the pressure created by the shock wave is not enough to penetrate thick armor, but some deflection is possible. With the thickening of the armor and the strengthening of the design of armored vehicles, it was necessary to increase the amount of explosives in the projectile by increasing its size (caliber, etc.) or developing new substances, which would be costly and inconvenient. By the way, this applies not only to ships, but also to land armored vehicles.

Initially, the first tanks during the First World War could be fought high-explosive fragmentation projectiles since the tanks had bulletproof thin armor only 10-20 mm thick, which was also connected with rivets, since at that time (the beginning of the 20th century) the technology for welding solid armored hulls of tanks and armored vehicles had not yet been worked out. It was enough 3 - 4 kg of explosives with a direct hit to put such a tank out of action. In this case, the shock wave simply tore or pressed the thin armor inside the vehicle, which led to damage to equipment or the death of the crew.

An armor-piercing projectile is a kinetic means of hitting a target - that is, it ensures defeat due to the energy of the impact of the projectile, and not the explosion. In armor-piercing projectiles, energy is actually concentrated at its tip, where a sufficiently large pressure is created on a small area of the surface, and the load significantly exceeds the tensile strength of the armor material. As a result, this leads to the introduction of the projectile into the armor and its penetration. Kinetic ammo were the first mass anti-tank weapon, which began to be used in series in various wars. The impact energy of the projectile depends on the mass and its speed at the moment of contact with the target. The mechanical strength, the density of the material of an armor-piercing projectile are also critical factors on which its effectiveness depends. For many years of wars, various types of armor-piercing shells have been developed, differing in design, and for more than a hundred years there has been a constant improvement of both shells and the armor of tanks and armored vehicles.

The first armor-piercing shells were all-steel solid projectile(blank) penetrating armor with impact force (thickness approximately equal to the caliber of the projectile)

Then the design began to get more complicated and for a long time the following scheme became popular: a rod / core made of hard hardened alloy steel covered in a shell of soft metal (lead or mild steel), or light alloy. The soft shell was needed to reduce wear on the gun barrel, and also because it was not practical to make the entire projectile from hardened alloy steel. The soft shell was crushed when hitting an inclined barrier, thereby preventing the projectile from ricocheting / slipping on the armor. The shell can also serve as a fairing at the same time (depending on the shape) that reduces air resistance during the flight of the projectile.

Another design of the projectile involves the absence of a shell and only the presence of a special soft metal cap as a projectile tip for aerodynamics and to prevent ricochet when hitting sloped armor.

The device of sub-caliber armor-piercing shells

The projectile is called sub-caliber because the caliber (diameter) of its combat / armor-piercing part is 3 less than the caliber of the gun (a - coil, b - streamlined). 1 - ballistic tip, 2 - pallet, 3 - armor-piercing core / armor-piercing part, 4 - tracer, 5 - plastic tip.

The projectile has rings around it made of soft metal, which are called leading belts. They serve to center the projectile in the barrel and obturate the barrel. Obturation is the sealing of the barrel bore when a gun (or a weapon in general) is fired, which prevents the powder gases (accelerating the projectile) from breaking through into the gap between the projectile itself and the barrel. Thus, the energy of the powder gases is not lost and is transferred to the projectile to the maximum possible extent.

Left- the dependence of the thickness of the armored barrier on its angle of inclination. A plate of thickness B1 inclined at some angle, a has the same resistance as a thicker plate of thickness B2 at right angles to the movement of the projectile. It can be seen that the path that the projectile must pierce increases with the increase in the slope of the armor.

On right- blunt projectiles A and B at the time of contact with sloping armor. Below - a sharp-headed arrow-shaped projectile. Due to the special shape of projectile B, its good engagement (biting) on sloping armor is visible, which prevents ricochet. Pointed Projectile less prone to ricochet due to its sharp shape and very high contact pressure when hitting armor.

The damaging factors when such projectiles hit the target are fragments and fragments of armor flying at high speed from its inner side, as well as the flying projectile itself or its parts. Particularly affected equipment located on the trajectory of breaking through the armor. In addition, due to the high temperature of the projectile and its fragments, as well as the presence of a large amount of flammable objects and materials inside the tank or armored vehicle, the risk of fire is very high. The image below shows how this happens:

A relatively soft projectile body is visible, crushed during impact and a hard-alloy core that penetrates armor. On the right, a stream of high-velocity fragments is visible from the inside of the armor as one of the main damaging factors. In all modern tanks there is a tendency for the most dense placement of internal equipment and crew to reduce the size and weight of tanks. back side of this medal is that if the armor is penetrated, it is almost guaranteed that some important equipment will be damaged or a crew member will be injured. And even if the tank is not destroyed, it usually becomes incapacitated. On modern tanks and armored vehicles, a non-combustible anti-fragmentation lining is installed on the inside of the armor. As a rule, this is a material based on Kevlar or other high-strength materials. Although it does not protect against the core of the projectile itself, it retains some of the armor fragments, thereby reducing the damage done and increasing the survivability of the vehicle and crew.

Above, on the example of an armored vehicle, one can see the armored effect of the projectile and fragments with and without the lining installed. On the left, fragments and the shell itself that pierced the armor are visible. On the right, the installed lining delays most armor fragments (but not the projectile itself), thereby reducing damage.

Even more efficient view shells are chamber shells. Chamber armor-piercing projectiles are distinguished by the presence of a chamber (cavity) inside the projectile filled with explosives and a delayed detonator. After penetrating the armor, the projectile explodes inside the object, thereby significantly increasing the damage dealt by fragments and a shock wave in a closed volume. In fact, this is an armor-piercing landmine.

One of the simple examples of a chamber projectile scheme

1 - soft ballistic shell, 2 - armor-piercing steel, 3 - explosive charge, 4 - bottom detonator, working with slowdown, 5 - front and rear leading belts (shoulders).

Chamber shells are not used today as anti-tank shells, since their design is weakened by an internal cavity with explosives and is not designed to penetrate thick armor, that is, a shell tank caliber(105 - 125 mm) will simply collapse in a collision with modern frontal tank armor (equivalent to 400 - 600 mm of armor and above). Such shells were widely used during the Second World War, since their caliber was comparable to the thickness of the armor of some tanks of that time. In naval battles of the past, chamber shells were used from a large caliber of 203 mm to a monstrous 460 mm (the battleship of the Yamato series), which could well penetrate thick ship steel armor comparable in thickness to their caliber (300 - 500 mm), or a layer of reinforced concrete and stone several meters.

Modern armor-piercing ammunition

Despite the fact that various types of anti-tank missiles were developed after the Second World War, armor-piercing ammunition remains one of the main anti-tank weapons. Despite the indisputable advantages of missiles (mobility, accuracy, homing capabilities, etc.), armor-piercing shells also have their advantages.

Their main advantage lies in the simplicity of design and, accordingly, production, which affects the lower price of the product.

In addition, an armor-piercing projectile, unlike an anti-tank missile, has a very high approach speed to the target (from 1600 m / s and above), it is impossible to “leave” it by maneuvering in time or hiding in a shelter (in a certain sense, when launching a rocket, such there is a possibility). In addition, an anti-tank projectile does not require the need to keep the target on sight, like many, though not all, ATGMs.

It is also impossible to create radio-electronic interference against an armor-piercing projectile due to the fact that it simply does not contain any electronic devices. In the case of anti-tank missiles, this is possible; such complexes as Shtora, Afghanit or Zaslon * are created specifically for this.

A modern armor-piercing projectile widely used in most countries of the world is actually a long rod made of a high-strength metal (tungsten or depleted uranium) or composite (tungsten carbide) alloy and rushing to the target at a speed of 1500 to 1800 m / s and higher. The rod at the end has stabilizers called plumage. The projectile is abbreviated as BOPS (Armor Piercing Feathered Sub-caliber Projectile). You can also just call it BPS (Armor Piercing Sub-caliber Projectile).

Almost all modern armor-piercing ammunition shells have the so-called. "Plumage" - tail flight stabilizers. The reason for the appearance of feathered shells lies in the fact that the shells of the old scheme described above after the Second World War have exhausted their potential. It was necessary to lengthen the shells for greater efficiency, but they lost their stability when big length. One of the reasons for the loss of stability was their rotation in flight (since most of the guns were rifling and informed the shells rotary motion). The strength of the materials of that time did not allow the creation of long projectiles with sufficient strength to penetrate thick composite (puff) armor. The projectile was easier to stabilize not by rotation, but by plumage. An important role in the appearance of plumage was also played by the appearance of smooth-bore guns, the shells of which could be accelerated to more high speeds than when using rifled guns, and the problem of stabilization in which began to be solved with the help of plumage (we will touch on the topic of rifled and smooth-bore guns in the next article).

Materials play a particularly important role in armor-piercing shells. Tungsten carbide** (composite material) has a density of 15.77 g/cm3, which is almost twice that of steel. It has great hardness, wear resistance and melting point (about 2900 C). Recently, heavier alloys based on tungsten and uranium have become especially widespread. Tungsten or depleted uranium has a very high density, which is almost 2.5 times higher than that of steel (19.25 and 19.1 g/cm3 versus 7.8 g/cm3 for steel) and, accordingly, greater mass and kinetic energy while maintaining minimum dimensions. Also, their mechanical strength (especially in bending) is higher than that of composite tungsten carbide. Thanks to these qualities, it is possible to concentrate more energy in a smaller volume of the projectile, that is, to increase the density of its kinetic energy. Also, these alloys have tremendous strength and hardness compared to even the strongest existing armor or specialty steels.

The projectile is called sub-caliber because the caliber (diameter) of its combat / armor-piercing part is less than the caliber of the gun. Typically, the diameter of such a core is 20 - 36 mm. Recently, projectile developers have been trying to reduce the diameter of the core and increase its length, if possible, maintain or increase mass, reduce drag during flight and, as a result, increase contact pressure at the point of impact with armor.

Uranium ammunition has 10 - 15% greater penetration with the same dimensions due to interesting feature alloy called self-sharpening. The scientific term for this process is "ablative self-sharpening". When passing tungsten projectile through the armor, its tip is deformed and flattened due to the enormous drag. When flattened, its contact area increases, which further increases the resistance to movement and, as a result, penetration suffers. When a uranium projectile passes through the armor at speeds greater than 1600 m/sec, its tip does not deform or flatten, but simply breaks down parallel to the movement of the projectile, that is, it peels off in parts and thus the rod always remains sharp.

In addition to the already listed damaging factors of armor-piercing shells, modern BPSs have a high incendiary ability when penetrating armor. This ability is called pyrophoricity - that is, self-ignition of projectile particles after breaking through armor ***.

125 mm BOPS BM-42 "Mango"

The design is a tungsten alloy core in a steel shell. Visible stabilizers at the end of the projectile (empennage). The white circle around the stem is the obturator. On the right, the BPS is equipped (drowned) inside the powder charge and in this form is delivered to the tank troops. On the left is the second powder charge with a fuse and a metal pan. As you can see, the whole shot is divided into two parts, and only in this form it is placed in the automatic loader of tanks of the USSR / RF (T-64, 72, 80, 90). That is, first the loading mechanism sends the BPS with the first charge, and then the second charge.

The photo below shows parts of the obturator at the moment of separation from the rod in flight. A burning tracer is visible at the bottom of the rod.

Interesting Facts

*The Russian Shtora system was designed to protect tanks from anti-tank guided missiles. The system determines that a laser beam is aimed at the tank, determines the direction of the laser source, and sends a signal to the crew. The crew can maneuver or hide the car in a shelter. The system is also connected to starting device smoke rockets that create a cloud that reflects optical and laser radiation, thereby knocking down the ATGM missile from the target. There is also the interaction of "Curtains" with searchlights - emitters that can interfere with the device of an anti-tank missile when directed at it. The effectiveness of the Shtora system against various latest-generation ATGMs is still in question. There are controversial opinions on this matter, however, as they say, its presence is better than complete absence. The last Russian tank "Armata" has a different system - the so-called. the Afganit complex active protection system, which, according to the developers, is capable of intercepting not only anti-tank missiles, but also armor-piercing shells flying at speeds up to 1700 m/s (in the future it is planned to increase this figure to 2000 m/s). In turn, the Ukrainian development "Barrier" operates on the principle of detonating ammunition on the side of an attacking projectile (rocket) and informing it powerful impulse in the form of a shock wave and fragments. Thus, the projectile or missile deviates from the originally given trajectory, and is destroyed before meeting the target (or rather, its target). Judging by the technical characteristics, the most effective this system maybe against RPGs and ATGMs.

**Tungsten carbide is used not only for the manufacture of shells, but also for the manufacture of heavy-duty tools for working with extra hard steels and alloys. For example, an alloy called "Pobedit" (from the word "Victory") was developed in the USSR in 1929. It is a solid homogeneous mixture / alloy of tungsten carbide and cobalt in a ratio of 90:10. Products are obtained by powder metallurgy. Powder metallurgy is the process of obtaining metal powders and manufacturing various high-strength products from them with pre-calculated mechanical, physical, magnetic, and other properties. This process makes it possible to obtain products from mixtures of metals and non-metals that simply cannot be joined by other methods, such as fusion or welding. The mixture of powders is loaded into the mold of the future product. One of the powders is a binding matrix (something like cement), which will firmly connect all the smallest particles / grains of the powder to each other. Examples are nickel and cobalt powders. The mixture is pressed in special presses under pressure from 300 to 10,000 atmospheres. The mixture is then heated to a high temperature (70 to 90% of the melting point of the binder metal). As a result, the mixture becomes denser and the bond between the grains is strengthened.

***Pyrophoricity is the ability of a solid material to self-ignite in air in the absence of heating and being in a finely divided state. The property can manifest itself upon impact or friction. One material that satisfies this requirement well is depleted uranium. When breaking through the armor, part of the core will just be in a finely divided state. Add to this also high temperature in the place where the armor was broken, the impact itself and the friction of many particles and we get ideal conditions for ignition. Special additives are also added to tungsten alloys of shells to make them more pyrophoric. As the simplest example of pyrophoricity in everyday life, one can cite the silicon of lighters, which are made of an alloy of cerium metal.

basic information

Armor-piercing sub-caliber projectile and its description

The action of a sub-caliber projectile

Varieties of PB shells

Currently, several effective designs of sub-caliber projectiles have been developed, which are used by the armed forces of various countries. In particular, we are talking about the following:

With non-separable tray. The projectile passes all the way to the target as a single whole. Only the core is involved in the penetration. This solution has not received sufficient distribution due to increased aerodynamic drag. As a result, the armor penetration rate and accuracy drop significantly with the distance to the target.
With non-detachable tray for conical implements. The essence of this solution is that when passing through the conical shaft, the pallet is crushed. This allows you to reduce aerodynamic drag.
Sub-caliber projectile with detachable pallet. The bottom line is that the pallet is torn off by air forces or by centrifugal forces (with a rifled gun). This allows you to significantly reduce air resistance in flight.

About cumulatives

For the first time, such ammunition was used by Nazi Germany in 1941. At that time, the USSR did not expect the use of such shells, since their principle of operation, although known, was not yet in service. The key feature of such projectiles was that they had high armor penetration due to the presence of instantaneous fuses and a cumulative recess. The problem, which was encountered for the first time, was that the projectile rotated during the flight. This led to the dispersion of the cumulative arrow and, as a result, reduced armor penetration. To eliminate the negative effect, it was proposed to use smoothbore guns.

Some interesting facts

Conclusion

A cumulative sub-caliber projectile is somewhat similar to a conventional sub-caliber. But in its body it has a fuse and an explosive. When armor is penetrated by such ammunition, a destructive effect is provided both on equipment and manpower. Currently, the most common shells for cannons with a caliber of 115, 120, 125 mm, as well as artillery pieces of 90, 100 and 105 mm. In general, this is all the information on this topic.