What is sub-caliber ammunition. Armor-piercing projectile. Armor-piercing caliber shells

Armor-piercing feathered sub-caliber projectile (arrow-shaped feathered projectile) - a type of projectile for barreled weapons, stabilized in flight due to aerodynamic forces (similar to stabilization in flight of an arrow). This circumstance distinguishes this type of ammunition from projectiles stabilized in flight by rotation due to gyroscopic forces. Arrow-shaped feathered projectiles can be used both in hunting and military firearms, and in cannon artillery. The main area of application of such projectiles is the destruction of heavily armored vehicles (in particular, tanks). Arrow-shaped feathered projectiles are usually kinetic-action ammunition, but may also contain an explosive charge.

120 mm shots of the Israeli company IMI. In the foreground is an M829 shot (USA), manufactured by IMI under license.

Terminology

Armor-piercing feathered under caliber shells(arrow type) can be abbreviated as BOPS, OBPS, OPS, BPS. Currently, the abbreviation BPS is also applied to feathered sabot arrow-shaped projectiles, although it should be correctly used to designate sabot armor-piercing projectiles of the usual elongation for rifled artillery projectiles. The name of the armor-piercing feathered arrow-shaped ammunition applicable to rifled and smoothbore artillery systems.

Device

Ammunition of this type They consist of an arrow-shaped feathered projectile, the body (body) of which (or the core inside the body) is made of a durable and high-density material, and the feathers are made of traditional structural alloys. The materials most used for the body include heavy alloys (of the VNZh type, etc.) and compounds (tungsten carbide), uranium alloys (for example, the American Stabilloy alloy or the domestic analogue of the UNC alloy type). The plumage is made of aluminum alloys or steel.

With the help of annular grooves (forgings), the BOPS body is connected to a sector pallet made of steel or high-strength aluminum alloys (type V-95, V-96Ts1 and similar). A sector pallet is also called a master device (VU) and consists of three or more sectors. The pallets are fastened to each other by leading belts made of metals or plastics and in this form are finally fixed in a metal sleeve or in the body of a burning sleeve. After leaving the gun barrel, the sector pallet is separated from the body of the BOPS under the action of the oncoming air flow, breaking the leading belts, while the body of the projectile itself continues to fly towards the target. Dropped sectors, having high aerodynamic drag, slow down in the air and fall at some distance (from hundreds of meters to more than a kilometer) from the muzzle of the gun. In the event of a miss, the BOPS itself, which has low aerodynamic drag, can fly away to a distance of 30 to more than 50 km from the muzzle of the gun.

The designs of modern BOPS are extremely diverse: the bodies of shells can be either monolithic or composite (a core or several cores in a shell, as well as longitudinally and transversely multilayered), plumage can be almost equal to the caliber of an artillery gun or sub-caliber, made of steel or light alloys. Master devices (VU) may have a different principle of distribution of the gas pressure action vector into sectors (VU of the “expanding” or “clamping” type), different amount sectors, made of steel, light alloys, as well as composite materials - for example, carbon composites or aramid composites. Ballistic tips and dampers can be installed in the head parts of the BOPS bodies. Additives can be added to the material of tungsten alloy cores to increase the pyrophoricity of the cores. Tracers can be installed in the tail parts of the BOPS.

The mass of BOPS bodies with plumage ranges from 3.6 kg in old models to 5-6 kg or more in models for advanced tank guns of 140-155 mm caliber.

The diameter of BOPS bodies without plumage ranges from 40 mm in older models to 22 mm or less in new promising BOPS with a large elongation. The elongation of BOPS is constantly increasing and ranges from 10 to 30 or more.

In the USSR and Russia, several types of BOPS are widely known, created at different times and having proper names, which originated from the name / cipher R & D . The BOPS are listed below in chronological order from oldest to newest. The device and material of the BOPS body are briefly indicated:

"Hairpin" 3BM-23 - a small core of tungsten carbide in the head of the steel body (1976);
"Nadfil-2" 3BM30 - uranium alloy (1982);
"Hope" 3BM-27 - a small tungsten alloy core in the tail section of a steel body (1983);
"Vant" 3BM-33 - a monolithic body made of a uranium alloy (1985);
"Mango" 3BM-44 - two elongated tungsten alloy cores in a steel body jacket (1986);
"Lead" 3BM-48 - a monolithic body made of a uranium alloy (1991);
Anker 3BM39 (1990s);
"Lekalo" 3BM44 M? - improved alloy (details unknown) (1997); perhaps this BOPS is called the "Projectile of increased power";
"Lead-2" - judging by the index, a modified projectile with a uranium core (details unknown).

Other BOPS also have proper names. For example, a 100 mm anti-tank smoothbore gun has the Valshchik ammunition, a 115 mm tank gun has the Kamerger ammunition, etc.

Armor penetration indicators

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This mark is set July 13, 2012.

Comparative evaluation of armor penetration indicators is associated with significant difficulties. Enough influence on the assessment of armor penetration indicators different techniques BOPS tests in different countries, the lack of a standard type of armor for testing in different countries, different conditions placement of armor (compact or spaced apart), as well as constant manipulations by developers of all countries with firing ranges of test armor, armor installation angles before testing, various statistical methods for processing test results. As a test material in Russia and NATO countries, homogeneous rolled armor is adopted; composite targets are used to obtain more accurate results. For example, for testing Russian shells, the P11 multilayer barrier developed at the Research Institute of Steel is used, imitating the frontal armor of the M1 Abrams tank. However, the real indicators of armor resistance composite armor and equivalent homogeneous armor still sometimes differ, which makes it difficult to accurately assess the armor penetration of a particular projectile. In addition, the characteristics of armor penetration, as well as the protection parameters of armored vehicles, are traditionally classified.

As an example, we can take the Spanish BOPS guns of the 105 mm caliber of the company "Empersa Nacional Santa Barbara", which at a speed of 1500 m / s from a distance of 5000 m pierces a NATO standard target at an angle of 60 ° from the line of fire and consisting of an armor plate 120 mm thick and ten additional armor plates of 10 mm, located at a distance of 10 mm from each other.

According to published data, an increase in the elongation of the flight part to a value of 30 made it possible to increase the relative thickness of RHA-standard rolled homogeneous armor (the ratio of armor thickness to gun caliber) to 5.0 in caliber 105 mm, and 6.8 in caliber 120 mm.

History

The emergence of BOPS was associated with insufficient armor penetration of conventional armor-piercing and sub-caliber shells for rifled artillery pieces in the years after World War II. Attempts to increase the specific load (that is, to lengthen their core) in sub-caliber projectiles ran into the phenomenon of loss of stabilization by rotation with an increase in the length of the projectile over 6-8 calibers. The strength of modern materials did not allow more angular velocity projectile rotation.

Arrow-shaped and feathered projectiles for ultra-long-range guns

In the rocket and artillery design bureau of the Peenemünde training ground Peenemünde-Heeresversuchsanstalt by the end of World War II, the German designer Hanns Gessner designed a series of arrow-shaped feathered shells of the PPG index (Peenemünder Pfeilgeschosse) for smooth-bore 310 mm caliber barrels from Krupp and Hanomag, mounted on a carriage of a 28-cm ultra-long-range railway installation K5 (E). The 310-mm high-explosive fragmentation projectile index Sprenge-Granate 4861 had a length of 2012 mm and a mass of 136 kg. The arrow body diameter was 120 mm, the number of stabilizer feathers was 4 pcs. The initial speed of the projectile is 1420 m / s, the mass of the explosive charge is 25 kg, the firing range is 160 km. The shells were used against the Anglo-American troops in the battles near Bonn.

Experiments with arrow-shaped feathered sub-caliber projectiles for high-altitude anti-aircraft artillery were carried out at a training ground near the Polish city of Blizna under the guidance of designer R. Herman ( R. Hermann). Anti-aircraft guns of 103 mm caliber with a barrel length of up to 50 calibers were tested. During the tests, it turned out that arrow-shaped feathered projectiles, which reached very high speeds due to their small mass, have insufficient fragmentation action due to the impossibility of placing a significant explosive charge in them. In addition, they demonstrated extremely low accuracy due to rarefied air at high altitudes and, as a result, insufficient aerodynamic stabilization. After it became clear that swept finned shells were not applicable for anti-aircraft fire, attempts were made to use high-velocity finned piercing shells to fight tanks. The work was stopped due to the fact that serial anti-tank and tank guns at that time had sufficient armor penetration, and the Third Reich was living out its last days.

Arrow-shaped bullets of handguns

Russia is developing arrow-shaped (needle-shaped) underwater ammunition without plumage, which are part of the SPS cartridges of 4.5 mm caliber (for special underwater pistol SPP-1; SPP-1M) and MPS cartridges of 5.66 mm caliber (for special underwater machine APS). Non-feathered arrow-shaped bullets for underwater weapons, stabilized in water by a cavitation cavity, practically do not stabilize in the air and require not regular, but special weapons for use under water.

Currently, the most promising underwater-air ammunition, which can be fired with equal efficiency both under water at a depth of up to 50 m, and in air, are cartridges for regular (serial) machine guns and assault rifles, equipped with Polotnev's arrow-shaped feathered bullet, developed at the Federal State Unitary Enterprise "TsNIIKhM". Stabilization of Polotnev's bullets under water is carried out by the cavitation cavity, and in air - by the plumage of the bullet.

MOSCOW, July 23 - RIA Novosti, Andrey Kots. If modern tank fired with an armor-piercing "blank" of the times of the Second World War, then, most likely, only a dent will remain at the site of the hit - penetrating through is practically impossible. The "puff" used today composite armor confidently holds such a blow. But it can still be pierced with an "awl". Or "crowbar", as the tankers themselves call armor-piercing feathered sub-caliber shells (BOPS). About how these munitions work - in the material of RIA Novosti.

Awl instead of a sledgehammer

From the name it is clear that the sub-caliber ammunition is a projectile with a caliber noticeably smaller than the caliber of the gun. Structurally, this is a "coil" with a diameter equal to the diameter of the barrel, in the center of which is the same tungsten or uranium "scrap" that hits the enemy's armor. When leaving the bore, the coil, which provided the core with sufficient kinetic energy and accelerated it to the desired speed, is divided into parts under the action of oncoming air flows, and a thin and strong feathered pin flies at the target. In a collision due to the smaller resistivity it penetrates armor much more effectively than a thick monolithic blank.

The armored impact of such a "scrap" is colossal. Due to the relatively small mass - 3.5-4 kilograms - the core of the sub-caliber projectile immediately after the shot accelerates to a significant speed - about 1500 meters per second. When hitting the armor plate, it punches a small hole. The kinetic energy of the projectile is partly used to destroy armor, and partly converted into heat. Red-hot fragments of the core and armor go into the armored space and spread like a fan, hitting the crew and internal mechanisms of the vehicle. This creates multiple fires.

An accurate hit of the BOPS can disable important components and assemblies, destroy or seriously injure crew members, jam the turret, break through fuel tanks, undermine the ammunition rack, destroy the undercarriage. Structurally, modern sabots are very different. Projectile bodies are both monolithic and composite - a core or several cores in a shell, as well as longitudinally and transversely multilayered, with various types of plumage.

Leading devices (those same "coils") have different aerodynamics, they are made of steel, light alloys, and composite materials - for example, carbon composites or aramid composites. Ballistic tips and dampers can be installed in the head parts of the BOPS. In a word, for every taste - for any gun, for certain conditions of tank combat and a specific target. The main advantages of such ammunition are high armor penetration, high flight speed, low sensitivity to dynamic protection, low vulnerability to active protection systems, which simply do not have time to react to a fast and inconspicuous "arrow".

"Mango" and "Lead"

For 125 mm smoothbore guns domestic tanks back in Soviet times, they developed a wide range of feathered "armor-piercing". They were engaged after the appearance of the potential enemy tanks M1 Abrams and Leopard-2. The army, like air, needed shells capable of hitting new types of reinforced armor and overcoming dynamic protection.

One of the most common BOPS in the arsenal of Russian T-72, T-80 and T-90 tanks is the ZBM-44 "Mango" high-power projectile, which was put into service in 1986. Have enough ammo complex structure. A ballistic tip is installed in the head part of the swept body, under which there is an armor-piercing cap. Behind him is an armor-piercing damper, also playing important role in penetration. Immediately after the damper are two tungsten alloy cores held inside by a light-alloy metal jacket. When a projectile collides with an obstacle, the shirt melts and releases cores that "bite" into the armor. In the tail of the projectile there is a stabilizer in the form of a plumage with five blades, at the base of the stabilizer there is a tracer. This "scrap" weighs only about five kilograms, but is capable of penetrating almost half a meter of tank armor at a distance of up to two kilometers.

The newer ZBM-48 "Lead" was put into service in 1991. Standard Russian tank autoloaders are limited by the length of the projectiles, so Lead is the most massive domestic tank ammunition of this class. The length of the active part of the projectile is 63.5 centimeters. The core is made of a uranium alloy, it has a high elongation, which increases penetration, and also reduces the impact of dynamic protection. After all, the longer the projectile, the smaller part of it interacts with passive and active obstacles at a certain point in time. Sub-caliber stabilizers improve the accuracy of the projectile, and a new composite "coil" drive device is also used. BOPS "Lead" is the most powerful serial projectile for 125-mm tank guns, capable of competing with leading Western models. The average armor penetration on a homogeneous steel plate from two kilometers is 650 millimeters.

This is not the only such development of the domestic defense industry - the media reported that specifically for the latest T-14 "Armata" tank, BOPS "Vacuum-1" with a length of 900 millimeters were created and tested. Their armor penetration came close to a meter.

It is worth noting that probable adversary also does not stand still. Back in 2016, Orbital ATK launched a full-scale production of an advanced armor-piercing feathered sub-caliber projectile with a fifth-generation M829A4 tracer for the M1 tank. According to the developers, the ammunition penetrates 770 millimeters of armor.

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 on the entire load, thereby providing initial speed flight. 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 high degree Pyrophoric depleted uranium causes numerous fires, 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. 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. 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.

IN War Thunder implemented many types of shells, each of which has its own characteristics. In order to competently compare different shells, choose the main type of ammunition before the battle, and in battle for different purposes in different situations to use suitable projectiles, you need to know the basics of their device and principle of operation. This article talks about the types of projectiles and their design, as well as gives advice on their use in combat. Do not neglect this knowledge, because the effectiveness of the weapon largely depends on the shells for it.

Types of tank ammunition

Armor-piercing caliber shells

Chamber and solid armor-piercing shells

As the name implies, the purpose of armor-piercing shells is to penetrate armor and thereby hit a tank. Armor-piercing shells are of two types: chamber and solid. Chamber shells have a special cavity inside - a chamber, in which an explosive is located. When such a projectile penetrates the armor, the fuse is triggered and the projectile explodes. The crew of an enemy tank is hit not only by armor fragments, but also by explosions and fragments of a chamber shell. The explosion does not occur immediately, but with a delay, thanks to which the projectile has time to fly into the tank and explode there, causing the most damage. In addition, the sensitivity of the fuse is set to, for example, 15 mm, that is, the fuse will only work if the thickness of the armor being penetrated is above 15 mm. This is necessary so that the chamber projectile explodes in the fighting compartment when it breaks through the main armor, and does not cock against the screens.

A solid projectile does not have a chamber with an explosive, it is just a metal blank. Of course, solid shells deal much less damage, but they penetrate a greater thickness of armor than similar chamber shells, since solid shells are stronger and heavier. For example, the armor-piercing chamber projectile BR-350A from the F-34 cannon pierces 80 mm at a right angle at close range, and the solid BR-350SP projectile as much as 105 mm. The use of solid projectiles is very typical for British school tank building. Things got to the point that the British removed explosives from American 75-mm chamber shells, turning them into solid ones.

The lethal force of solid shells depends on the ratio of the thickness of the armor and the armor penetration of the shell:

If the armor is too thin, then the projectile will pierce through it and damage only those elements that it hits along the way.
If the armor is too thick (on the border of penetration), then small non-lethal fragments are formed that will not cause much harm.
Maximum armor action - in case of penetration of sufficiently thick armor, while the penetration of the projectile should not be completely used up.

Thus, in the presence of several solid shells, the best armor action will be with the one with greater armor penetration. As for chamber shells, the damage also depends on the amount of explosive in TNT equivalent, as well as on whether the fuse worked or not.

Sharp-headed and blunt-headed armor-piercing shells

An oblique blow to the armor: a - a sharp-headed projectile; b - blunt projectile; c - arrow-shaped sub-caliber projectile

Armor-piercing shells are divided not only into chamber and solid shells, but also into sharp-headed and dumb-headed ones. Pointed shells pierce thicker armor at a right angle, since at the moment of impact with the armor, all the impact force falls on a small area of the armor plate. However, the efficiency of work on sloping armor in sharp-headed projectiles is lower due to a greater tendency to ricochet at large angles of impact with the armor. Conversely, blunt-headed shells penetrate thicker armor at an angle than sharp-headed shells, but have less armor penetration at right angles. Let's take for example the armor-piercing chamber shells of the T-34-85 tank. At a distance of 10 meters, the BR-365K sharp-headed projectile penetrates 145 mm at a right angle and 52 mm at an angle of 30 °, and the BR-365A blunt-headed projectile penetrates 142 mm at a right angle, but 58 mm at an angle of 30 °.

In addition to sharp-headed and blunt-headed shells, there are sharp-headed shells with an armor-piercing tip. When meeting armor plate at a right angle, such a projectile works like a sharp-headed one and has good armor penetration compared to a similar blunt-headed projectile. When hitting sloping armor, the armor-piercing tip “bites” the projectile, preventing ricochet, and the projectile works like a dumb-ass.

However, sharp-headed shells with an armor-piercing tip, like blunt-headed shells, have a significant drawback - greater aerodynamic resistance, due to which armor penetration drops more at a distance than sharp-headed shells. To improve aerodynamics, ballistic caps are used, due to which armor penetration is increased at medium and long distances. For example, on the German 128 mm KwK 44 L/55 gun, two armor-piercing chamber shells are available, one with a ballistic cap and the other without it. Armor-piercing sharp-headed projectile with an armor-piercing tip PzGr at a right angle pierces 266 mm at 10 meters and 157 mm at 2000 meters. And here armor-piercing projectile with an armor-piercing tip and a ballistic cap, the PzGr 43 pierces 269 mm at 10 meters and 208 mm at 2000 meters at a right angle. In close combat, there are no special differences between them, but at long distances the difference in armor penetration is huge.

Armor-piercing chamber shells with an armor-piercing tip and a ballistic cap are the most versatile type of armor-piercing ammunition that combines the advantages of sharp-headed and blunt-headed projectiles.

Table of armor-piercing shells

Sharp-headed armor-piercing shells can be chamber or solid. The same applies to blunt-headed shells, as well as sharp-headed shells with an armor-piercing tip, and so on. Let's put it all together possible options to the table. Under the icon of each projectile, the abbreviated names of the projectile type are written in English terminology, these are the terms used in the book "WWII Ballistics: Armor and Gunnery", according to which many shells in the game are configured. If you hover over the abbreviated name with the mouse cursor, a hint with decoding and translation will appear.

	dumb-headed (with ballistic cap)	sharp-headed	sharp-headed with armor-piercing tip	sharp-headed with armor-piercing tip and ballistic cap
Solid projectile	APBC	AP	APC	APCBC
Chamber projectile		APHE	APHEC

Sub-caliber shells

Coil sub-caliber projectiles

The action of the sub-caliber projectile:
1 - ballistic cap
2 - body
3 - core

Armor-piercing caliber shells have been described above. They are called caliber because the diameter of their warhead is equal to the caliber of the gun. There are also armor-piercing sub-caliber shells, the warhead diameter of which is smaller than the caliber of the gun. The simplest type of sub-caliber projectiles is coil (APCR - Armor-Piercing Composite Rigid). The coil sub-caliber projectile consists of three parts: a body, a ballistic cap and a core. The body serves to disperse the projectile in the barrel. At the moment of meeting with the armor, the ballistic cap and the body are crushed, and the core pierces the armor, hitting the tank with shrapnel.

At close range, sub-caliber shells penetrate thicker armor than caliber shells. Firstly, the sabot projectile is smaller and lighter than a conventional armor-piercing projectile, thanks to which it accelerates to higher speeds. Secondly, the core of the projectile is made of hard alloys with a high specific gravity. Thirdly, due to the small size of the core at the moment of contact with the armor, the impact energy falls on a small area of the armor.

But coil sub-caliber shells also have significant drawbacks. Due to their relatively light weight, sub-caliber shells are ineffective at long distances, they lose energy faster, hence the drop in accuracy and armor penetration. The core does not have an explosive charge, therefore, in terms of armor action, sub-caliber shells are much weaker than chamber shells. Finally, sub-caliber shells do not work well against sloped armor.

Coil sub-caliber shells were effective only in close combat and were used in cases where enemy tanks were invulnerable against caliber armor-piercing shells. 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.

Sub-caliber projectiles with a detachable pallet

APDS projectile and its core

Sectional view of an APDS projectile, showing the ballistic-tipped core

Armor-Piercing Discarding Sabot (APDS) - a further development of the design of sabot projectiles.

Coil sub-caliber projectiles had a significant drawback: the hull flew along with the core, increasing aerodynamic drag and, as a result, a drop in accuracy and armor penetration at a distance. For sub-caliber shells with a detachable pallet, a detachable pallet was used instead of the body, which first dispersed the projectile in the gun barrel, and then separated from the core by air resistance. The core flew to the target without a pallet and, due to the significantly lower aerodynamic resistance, did not lose armor penetration at a distance as quickly as coil sub-caliber shells.

During the Second World War, sub-caliber shells with a detachable pallet were distinguished by record-breaking armor penetration and flight speed. For example, the Shot SV Mk.1 sub-caliber projectile for the 17-pounder accelerated to 1203 m/s and pierced 228 mm of soft armor at a right angle at 10 meters, while the Shot Mk.8 armor-piercing caliber projectile only 171 mm under the same conditions.

Sub-caliber feathered shells

Separation of the pallet from BOPS

BOPS projectile

Armor-Piercing Fin-Stabilized Discarding Sabot (APFSDS - Armor-Piercing Fin-Stabilized Discarding Sabot) - the most modern type of armor-piercing projectiles designed to destroy heavily armored vehicles protected the latest species armor and active protection.

These projectiles are a further development of sabot projectiles with a detachable pallet, they are even longer and have a smaller cross section. Spin stabilization is not very effective for high aspect ratio projectiles, so armor piercing finned sabots (BOPS for short) are stabilized by the fins and are generally used to fire smoothbore guns (however, early BOPS and some modern ones are designed to fire rifled guns).

Modern BOPS projectiles have a diameter of 2-3 cm and a length of 50-60 cm. To maximize the specific pressure and kinetic energy of the projectile, high-density materials are used in the manufacture of ammunition - tungsten carbide or an alloy based on depleted uranium. The muzzle velocity of the BOPS is up to 1900 m / s.

Concrete-piercing projectiles

The concrete projectile is artillery shell, designed to destroy long-term fortifications and solid buildings of capital construction, as well as to destroy manpower sheltered in them and military equipment enemy. Often, concrete-piercing shells were used to destroy concrete pillboxes.

In terms of design, concrete-piercing shells occupy an intermediate position between armor-piercing chamber and high-explosive fragmentation shells. Compared to high-explosive fragmentation projectiles of the same caliber, with a close destructive potential of the explosive charge, concrete-piercing ammunition has a more massive and durable body, which allows them to penetrate deep into reinforced concrete, stone and brick barriers. Compared to armor-piercing chamber shells, concrete-piercing shells have more explosives, but a less durable body, so concrete-piercing shells are inferior to them in armor penetration.

The G-530 concrete-piercing projectile weighing 40 kg is included in the ammunition load of the KV-2 tank, the main purpose of which was the destruction of pillboxes and other fortifications.

HEAT rounds

Rotating HEAT projectiles

The device of the cumulative projectile:
1 - fairing
2 - air cavity
3 - metal cladding
4 - detonator
5 - explosive
6 - piezoelectric fuse

The cumulative projectile (HEAT - High-Explosive Anti-Tank) in terms of the principle of operation differs significantly from kinetic ammunition, which includes conventional armor-piercing and sub-caliber projectiles. It is a thin-walled steel projectile filled with a powerful explosive - RDX, or a mixture of TNT and RDX. In front of the projectile in explosives there is a goblet-shaped or cone-shaped recess lined with metal (usually copper) - a focusing funnel. The projectile has a sensitive head fuse.

When a projectile collides with armor, an explosive is detonated. Due to the presence of a focusing funnel in the projectile, part of the explosion energy is concentrated at one small point, forming a thin cumulative jet consisting of the metal of the lining of the same funnel and explosion products. The cumulative jet flies forward at great speed (approximately 5,000 - 10,000 m / s) and passes through the armor due to the enormous pressure it creates (like a needle through oil), under the influence of which any metal enters a state of superfluidity or, in other words, leads itself as a liquid. The armored damaging effect is provided both by the cumulative jet itself and by hot drops of pierced armor squeezed inward.

The most important advantage of a HEAT projectile is that its armor penetration does not depend on the velocity of the projectile and is the same at all distances. That is why cumulative shells were used on howitzers, since conventional armor-piercing shells would be ineffective for them due to their low flight speed. But the cumulative shells of the Second World War also had significant drawbacks that limited their use. The rotation of the projectile at high initial speeds made it difficult to form a cumulative jet, as a result, the cumulative projectiles had a low initial speed, a small effective range and high dispersion, which was also facilitated by the shape of the projectile head, which was not optimal from the point of view of aerodynamics. The manufacturing technology of these shells at that time was not sufficiently developed, so their armor penetration was relatively low (approximately corresponded to the caliber of the projectile or slightly higher) and was unstable.

Non-rotating (feathered) cumulative projectiles

Non-rotating (feathered) cumulative projectiles (HEAT-FS - High-Explosive Anti-Tank Fin-Stabilised) are further development cumulative ammunition. Unlike early cumulative projectiles, they are stabilized in flight not by rotation, but by folding fins. The lack of rotation improves the formation of a cumulative jet and significantly increases armor penetration, while removing all restrictions on the speed of the projectile, which can exceed 1000 m/s. So, for early cumulative shells, typical armor penetration was 1-1.5 calibers, while for post-war shells it was 4 or more. However, feathered projectiles have a slightly lower armor effect compared to conventional HEAT projectiles.

Fragmentation and high-explosive shells

High-explosive shells

A high-explosive fragmentation projectile (HE - High-Explosive) is a thin-walled steel or cast iron projectile filled with an explosive (usually TNT or ammonite), with a head fuse. Upon hitting the target, the projectile immediately explodes, hitting the target with fragments and an explosive wave. Compared with concrete-piercing and armor-piercing chamber shells, high-explosive fragmentation projectiles very thin walls, but more explosive.

The main purpose of high-explosive fragmentation shells is to defeat enemy manpower, as well as unarmored and lightly armored vehicles. High-explosive high-explosive shells of large caliber can be used very effectively to destroy lightly armored tanks and self-propelled guns, as they break through relatively thin armor and incapacitate the crew with the force of the explosion. Tanks and self-propelled guns with anti-projectile armor are resistant to high-explosive fragmentation shells. However, large-caliber projectiles can even hit them: the explosion destroys the tracks, damages the gun barrel, jams the turret, and the crew is injured and shell-shocked.

Shrapnel shells

The shrapnel projectile is a cylindrical body, divided by a partition (diaphragm) into 2 compartments. An explosive charge is placed in the bottom compartment, and spherical bullets are in the other compartment. A tube filled with a slowly burning pyrotechnic composition passes along the axis of the projectile.

The main purpose of the shrapnel projectile is to defeat the enemy's manpower. It happens in the following way. At the moment of the shot, the composition in the tube ignites. Gradually, it burns out and transfers the fire to the explosive charge. The charge ignites and explodes, squeezing out a partition with bullets. The head of the projectile comes off and the bullets fly out along the axis of the projectile, deviating slightly to the sides and hitting the enemy infantry.

In the absence of armor-piercing shells in the early stages of the war, gunners often used shrapnel shells with a tube set "on impact". In terms of its qualities, such a projectile occupied an intermediate position between high-explosive fragmentation and armor-piercing, which is reflected in the game.

Armor-piercing shells

Armor-piercing high-explosive projectile (HESH - High Explosive Squash Head) - post-war type anti-tank projectile, the principle of operation of which is based on the detonation of a plastic explosive on the surface of the armor, which causes the armor fragments on the back to break off and damage the fighting compartment of the vehicle. An armor-piercing high-explosive projectile has a body with relatively thin walls, designed for plastic deformation when it encounters an obstacle, as well as a bottom fuse. The charge of an armor-piercing high-explosive projectile consists of a plastic explosive that “spreads” over the surface of the armor when the projectile meets an obstacle.

After “spreading”, the charge is detonated by a slow-acting bottom fuse, which causes the destruction of the rear surface of the armor and the formation of spalls that can hit the internal equipment of the vehicle or crew members. In some cases, penetrating armor can also occur in the form of a puncture, a breach, or a broken plug. The penetrating ability of an armor-piercing high-explosive projectile depends less on the angle of the armor in comparison with conventional armor-piercing projectiles.

ATGM Malyutka (1 generation)

Shillelagh ATGM (2 generations)

Anti-tank guided missiles

anti-tank guided missile(ATGM) - a guided missile designed to destroy tanks and other armored targets. The former name of the ATGM is "anti-tank guided missile". ATGMs in the game are solid-propellant missiles equipped with on-board control systems (operating on the operator's commands) and flight stabilization, devices for receiving and decrypting control signals received via wires (or via infrared or radio command control channels). Warhead cumulative, with armor penetration of 400-600 mm. The flight speed of missiles is only 150-323 m / s, but the target can be successfully hit at a distance of up to 3 kilometers.

The game features ATGMs of two generations:

First generation (manual command system guidance)- in reality, they are manually controlled by the operator using a joystick, eng. MCLOS. In realistic and simulation modes, these missiles are controlled using the WSAD keys.
Second generation (semi-automatic command guidance system)- in reality and in all game modes, they are controlled by pointing the sight at the target, eng. SACLOS. The reticle in the game is either the center of the crosshair of the optical sight, or a large white round marker (reload indicator) in the third person view.

In arcade mode, there is no difference between the generations of rockets, they are all controlled with the help of a sight, like second-generation rockets.

ATGMs are also distinguished by the launch method.

1) Launched from the channel of the tank barrel. To do this, you need either a smooth barrel: an example is the smooth barrel of a 125-mm gun of the T-64 tank. Or a keyway is made in a rifled barrel, where a rocket is inserted, for example, in the Sheridan tank.
2) Launched from guides. Closed, tubular (or square), for example, like the RakJPz 2 tank destroyer with the HOT-1 ATGM. Or open, rail (for example, like the IT-1 tank destroyer with the 2K4 Dragon ATGM).

As a rule, the more modern and the more caliber ATGM - the more it penetrates. ATGMs were constantly improved - manufacturing technology, materials science, and explosives improved. The penetrating effect of ATGMs (as well as HEAT rounds) can be completely or partially neutralized by combined armor and dynamic protection. As well as special anti-cumulative armor screens located at some distance from the main armor.

Appearance and device of shells

Armor-piercing sharp-headed chamber projectile

Pointed Projectile with armor-piercing tip

Sharp-headed projectile with armor-piercing tip and ballistic cap

Armor-piercing blunt projectile with ballistic cap

Sub-caliber projectile

Sub-caliber projectile with detachable pallet

HEAT projectile

Non-rotating (feathered) cumulative projectile

A denormalization phenomenon that increases the path of a projectile through armor

Starting with game version 1.49, the effect of shells on sloped armor has been redesigned. Now the value of the reduced armor thickness (armor thickness ÷ cosine of the angle of inclination) is valid only for calculating the penetration of HEAT projectiles. For armor-piercing and especially sub-caliber shells, the penetration of sloping armor was significantly reduced due to the denormalization effect, when a short shell turns around during penetration, and its path in the armor increases.
So, at an angle of inclination of the armor of 60 °, penetration for all shells fell by about 2 times. Now this is true only for cumulative and armor-piercing high-explosive shells. For armor-piercing shells, penetration in this case drops by 2.3-2.9 times, for conventional sub-caliber shells - by 3-4 times, and for sub-caliber shells with a detachable pallet (including BOPS) - by 2.5 times.
List of shells in order of deterioration of their work on sloped armor:
1. Cumulative And armor-piercing high-explosive- the most efficient.
2. Armor-piercing blunt And armor-piercing sharp-headed with an armor-piercing tip.
3. Armor-piercing sub-caliber with detachable pallet And BOPS.
4. Armor-piercing sharp-headed And shrapnel.
5. Armor-piercing sub-caliber- the most inefficient.
Here, a high-explosive fragmentation projectile stands apart, in which the probability of penetrating the armor does not depend on its angle of inclination at all (provided that no ricochet has occurred).

Armor-piercing shells

For such projectiles, the fuse is cocked at the moment of penetration of the armor and undermines the projectile after a certain time, which ensures a very high armor effect. The parameters of the projectile indicate two important: fuse sensitivity and fuse delay.
If the thickness of the armor is less than the sensitivity of the fuse, then the explosion will not occur, and the projectile will work like a regular solid one, damaging only those modules that are in its path, or simply fly through the target without causing damage. Therefore, when firing at unarmored targets, chamber shells are not very effective (as well as all others, except for high-explosive and shrapnel).
The fuse delay determines the time after which the projectile will explode after breaking through the armor. Too little delay (in particular, for the Soviet MD-5 fuse) leads to the fact that when it hits hinged element tank (screen, track, undercarriage, caterpillar), the projectile explodes almost immediately and does not have time to penetrate the armor. Therefore, when firing at shielded tanks, it is better not to use such shells. Too much delay of the fuse can cause the projectile to go right through and explode outside the tank (although such cases are very rare).
If a chamber projectile is detonated in a fuel tank or in an ammunition rack, then with a high probability an explosion will occur and the tank will be destroyed.

Armor-piercing sharp-headed and blunt-headed projectiles

Depending on the shape of the armor-piercing part of the projectile, its tendency to ricochet, armor penetration and normalization differ. General rule: blunt-headed shells are best used on opponents with sloped armor, and sharp-headed ones - if the armor is not sloped. However, the difference in armor penetration in both types is not very large.
The presence of armor-piercing and / or ballistic caps significantly improves the properties of the projectile.

Sub-caliber shells

This type of projectile is characterized by high armor penetration at short distances and a very high flight speed, which makes it easier to shoot at moving targets.
However, when armor is penetrated, only a thin hard-alloy rod appears in the armored space, which causes damage only to those modules and crew members in which it hits (unlike an armor-piercing chamber projectile, which fills everything with fragments fighting compartment). Therefore, in order to effectively destroy a tank with a sub-caliber projectile, it is necessary to shoot at its weak spots: engine, ammo rack, fuel tanks. But even in this case, one hit may not be enough to disable the tank. If you shoot at random (especially at the same point), it may take a lot of shots to disable the tank, and the enemy may get ahead of you.
Another problem with sub-caliber projectiles is a strong loss of armor penetration with distance due to their low mass. Studying the armor penetration tables shows at what distance you need to switch to a regular armor-piercing projectile, which, in addition, has a much greater lethality.

HEAT rounds

The armor penetration of these shells does not depend on the distance, which allows them to be used with equal efficiency for both close and long-range combat. However, due to design features, HEAT rounds often have a lower flight speed than other types, as a result of which the shot trajectory becomes hinged, accuracy suffers, and it becomes very difficult to hit moving targets (especially at long distances).
The principle of operation of the cumulative projectile also determines its not very high damaging ability compared to the armor-piercing chamber projectile: the cumulative jet flies for a limited distance inside the tank and inflicts damage only to those components and crew members in which it directly hit. Therefore, when using a cumulative projectile, one should aim just as carefully as in the case of a sub-caliber one.
If the cumulative projectile hit not the armor, but the hinged element of the tank (screen, track, caterpillar, undercarriage), then it will explode on this element, and the armor penetration of the cumulative jet will significantly decrease (each centimeter of the jet flight in the air reduces armor penetration by 1 mm) . Therefore, other types of shells should be used against tanks with screens, and one should not hope to penetrate the armor with HEAT shells by shooting at the tracks, undercarriage and gun mantlet. Remember that a premature detonation of a projectile can cause any obstacle - a fence, a tree, any building.
HEAT shells in life and in the game have a high-explosive action, that is, they also work as high-explosive fragmentation shells of reduced power (a light body gives fewer fragments). Thus, large-caliber cumulative projectiles can be quite successfully used instead of high-explosive fragmentation when firing at lightly armored vehicles.

High-explosive shells

The striking ability of these shells depends on the ratio of the caliber of your gun and the armor of your target. Thus, shells with a caliber of 50 mm or less are only effective against aircraft and trucks, 75-85 mm - against light tanks with bulletproof armor, 122 mm - against medium tanks such as T-34, 152 mm - against all tanks, with the exception of head-on shooting at the most armored vehicles.
However, it must be remembered that the damage inflicted significantly depends on the specific point of impact, so there are cases when even a 122-152 mm caliber projectile causes very minor damage. And in the case of guns with a smaller caliber, in doubtful cases, it is better to use an armor-piercing chamber or shrapnel projectile, which have greater penetration and high lethality.

Shells - part 2

What is the best way to shoot? Overview tank shells by _Omero_