MAIN MENU SOLDIERS AT WAR DOCUMENTS BATTLES TANKS ARTILLERY 
| Definitions of the Soviet Ammunition |
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| MAIN MENU SOLDIERS AT WAR DOCUMENTS BATTLES TANKS ARTILLERY |
In artillery the "shot" term has two meanings: first, this is a known physical phenomenon of discharging a shot, second, a solid projectile designed to be discharged from a firearm or a gun. To discharge a shot from an artillery piece or to shoot a shot, one needs a complete piece of ammunition or a round.
A round usually consists of a projectile, fuse to explode it, powder charge to propel the projectile, cartridge which contains the charge and the means of ignition of the charge.
To make a shot from a gun, it is necessary at first to charge the gun. That is to enclose in the barrel of the gun a shell and a propellant charge. The propellant charge is a strictly known quantity of smokeless powder, which is applied to each shot.
Now, its time to add some basic definitions. How different parts of a shell call? I asked this question many peoples who're natively speaking English. And I've got completely different answers. So, I've chose one of them that seemed to me most simple.
Of course, some elements may looks slightly different or they may be absent at all, but I hope you've got the idea.
| A Fixed Round | |
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The types of propellant charges differ from preset to variable. The preset charges are used in guns charged with unitary or one-piece shells (like rifle rounds). In such a round the projectile is partially inserted into the top of a cartridge case on top of the propellant charge to make them into one unit. Such rounds are usually used in smaller calibre of guns. The reloading of such a weapon is done as a single action.
| A Semi-Fixed Round | |
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Veritable powder charge ammunition is loaded in a multi action process. The propellant charge consists of a main charge and additional charges. So it is possible to vary the amount of propellant in the charge by adding or subtracting the propellant units, thus varying the trajectory of the projectile. This type of ammunition consists of multiple parts, the projectile and a propellant charge. The guns using this type of ammunition are charged in two actions, first a shell is loaded then a propellant charge. |
| A Propellant-Bag Charge | |
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As well as in previous illustration, the elements of the ammunition are contained separately. The propellant charge is contained in so-called powder-bag. This type of ammunition is generally used in large caliber weapons and the projectile and the powder bag are loaded as part of a separate action. |
| Fragmentation Projectiles | |
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This type of ammunition is used to defeat "soft" targets. During the explosion, the round's case fragments and saturates the area with shrapnel in addition to explosion and a shock wave.
| High Explosive (HE) Projectiles |
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The High Explosive or HE projectiles are usually most effective in the large caliber of weapons. This is an ordinary shell which contains a warhead composed of a high explosive compound. Because the energy of the shell remains consistent, it can be fired at a lower velocity which allows for a larger warhead in most calibers. The shell consists of a thin-walled steel case, explosive charge and a fuse. The main destructive power of a HE shell comes from the shock wave of the explosive charge. The fuse is generally set in the nose or the base, and detonates automatically on impact. Although there are shells designed to detonate after a certain distance or in the air above the target, these are primarily the province of antiaircraft and artillery guns.
High Explosive Plastic is variation of the common high explosive round operates on the theory that it is more important to disable a tank by killing its crew rather than by penetrating its armor. It's also known as High Explosive Squash-Head (HESH). The warhead consists of a soft explosive in a thin shell that is designed to open on impact, spreading the explosive on the armor in the short microseconds of delay before the base-detonating fuse fires it off. This generally has little effect on the outer layers of armor, except for some possible cratering. On the inside of the tank, however, the blast often causes some of the interior layers of steel to break off and ricochet around inside of the vehicle. This has the primary purpose of killing the crew, and can also disable controls and instrumentation, making the vehicle inoperable.
The Russians widely used High Explosive Fragmentation projectiles. The fuse of the projectile could be set in two positions (different time delaying after projectile engages with surfase). The first position is for more explosive power but less number of fragments, the second position is for more number of fragments but less explosive power.
| Armor Piercing Projectiles |
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Armor piercing ammunition is used for the purpose of defeating the armor of AFVs (Armored Fighting Vehicles). Basically, armor piercing rounds are divided into two large groups - full caliber and sub-caliber APS (Armor Piercing Sub-caliber). Caliber rounds can have an explosive charge in them or can be solid. A solid round consists of a solid metal construction incased in a strong steel case. In such a round there is no explosive charge as it depends on kinetic energy for penetration of the AFV armor. Crew and the vital components of the AFV are destroyed as the result of penetration and fragmentation of the armor.
In a round with the explosive, the explosion of the charge after the kinetic penetration of the armor by the solid metal tip adds to the destruction of the internal components of the AFV.
The 'pure' Armour Piercing is an antitank round where the projectile is a full caliber projectile of high strength material, such as steel, which is either completely solid or which contains a small amount of high explosive. The latter type of projectile is sometimes referred to as APHE. The amount of explosive charge carried was small because the bulk of the mass was solid to achieve adequate penetration force. The explosive charge was designed to detonate after penetration of the target for maximum damage. Armies such as the German army never used solid AP projectiles so they generally referred to their basic antitank projectile as AP rather than APHE as there was no risk of confusion. At the same time, Soviet Union used solid AP rounds. Sometimes the term AP is used as a general term to describe any full caliber projectile, including APBC, APC and APCBC projectiles.
Armor Piercing High Explosive (APHE) is variation of the basic AP projectile which contains a small amount of high explosive. The amount of explosive carried was small because the bulk of the mass was solid to achieve adequate penetration. The explosive was designed to detonate after penetration of the target for maximum damage. USSR used APHE as well as pure (solid) AP rounds.
Armour Piercing Capped (APC) is an AP projectile with a metal piercing cap fitted over the nose. This directs the impact shock away from the tip of the projectile to the shoulders preventing the tip from shattering at high impact velocities and allows face hardened (FH) armour to be defeated. APC also allowed thicker slabs of overmatching homogeneous armour to be defeated without the shattering of the projectile. Often a ballistic cap is fitted over the piercing cap to improve flight characteristics and the round is then referred to as an APCBC projectile. USSR didn't use APC projectiles.
Armour Piercing with Ballistic Cap (APBC). An AP projectile with a truncated nose (as if the end had been sawn off) covered by a light weight ballistic cap to improve flight characteristics. The truncated nose has better penetration above certain velocities, particularly when it overmatches the target armour plate and when the plate is prone to brittle failure. This was a common projectile for the USSR in World War Two as they did not use APC projectiles until the 1950s.
Armour Piercing Capped with Ballistic Cap (APCBC). An APC projectile with a light weight ballistic cap fitted over the piercing cap (tip) to improve flight characteristics, as the optimum shape for the piercing cap is not usually the best for stable flight. USSR used APCBC projectiles during the WWII.
| Hyper-Velocity Armor Piercing (HVAP) or Armour Piercing Composite | |
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HVAP projectiles are intended to defeat heavily armored AFVs. In Russia they called "sub-caliber AP", the rest of world call it "Sabot". With the diameter of one third of the caliber, the core of this projectile is the main armor-penetrating component. HVAP projectiles consist of a soft case surrounding the heavy core and is toped with the ballistic tip. This type of a projectile doesn't have any explosive and the core is made out of high-density material. On the impact of the projectile, the soft casing collapses and the high-density core, having high amount of energy penetrates the armor. As the result of this, high amount of heat is generated and combined with the penetration and fragmentation of the armor the AFV is destroyed.
Such HVAP projectiles have substantially greater armor penetrating ability at the range of 1000 metres then caliber armor piercing ammunition. The Germans used the sub-caliber ammunition for the first time at the end of 1941, but the idea of such a projectile is not new. Such projectiles were available in USA in 1884 and were developed in Russia after the World War One.
The Armor Piercing Composite Rigid (APCR) projectile was designed to give a very high velocity and high penetration at short range without risk of shot shatter. Some techniques used to get this result included the German "squeeze-bore," which reduced the diameter of the bore over the length of the barrel to crush a thin metal skirt around the shot, a heavy core carried in a thin metal frame, a heavy shot surrounded by lighter metal such as aluminum or sintered iron, or a "shoe" used to carry the core shot which would fall off in flight (known as the "discarding sabot"). All of these methods required the use of a heavy center, normally made out of tungsten carbide, to get the highest velocity out of a very small, dense core. At longer ranges, these rounds proved to be less effective than ordinary APCBC, however, at close ranges they were very successful.
Armor Piercing Discarding Sabot (APDS) was developed to be the most effective method of firing a high-velocity heavy-cored round from a tank gun and was developed by the British at the end of the World War Two. Essentially, the heavy penetrator is held in a "shoe" made of some light material (aluminum, plastic, and even wood have been used), which is designed to fly off of the core, without disturbing its flight, shortly after leaving the muzzle. This type of projectile has become so powerful that it has replaced all other types of antitank projectile in some armies, and APDS projectiles have been made for older tank and antitank guns to extend their useful life.
A more modern version of such ammunition is Armor Piercing Fin Stabilized Discarding Sabot (APFSDS). Such projectiles have been designed to provide more stability when fired out of modern smoothbore tank and anti-tank guns. It consists of a sub-caliber, high density, fin stabilized dart and the sabot. The sabot falls away after the round exits the barrel of the weapon, leaving the long-rod penetrator to defeat the target. The most effective of the modern sabot projectiles is the Armor-Piercing Fin Stabilized Depleted Uranium Discarding Sabot (APFSDUDS), it used in the tank guns. The extreme velocity to which these projectiles are pushed can cause the penetrator to go in one side of a modern MBT and out the other.
| Shaped-Charge Anti-Tank Projectiles or HEAT | |
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HEAT ammunition is intended for direct engagement of enemy AFVs and vertical walls of the defensive structures.
HEAT warhead drastically differs in the way it uses to penetrate armor from standard kinetic penetrators. The armor-piercing action occurs not due to the impact or the kinetic energy of a round, but to the highly directed energy of the explosion, which occurs upon the impact of the HEAT warhead. HEAT has its roots in an explosive theory known as the Monroe Effect. This effect takes place when a hollow space is left in an explosive charge, causing the gases in that space to be turned into hot plasma by the blast. This plasma, when the space is given the proper shape, can become a high velocity jet capable of penetrating armor equal to 150-250% of the warhead diameter.
A small amount of explosive is placed in a hollow of the shell. As the round impacts the explosion occurs and is directed by the hollow, in a very narrow jet of super heated gasses, which burn through the armor. For this reason the HEAT rounds are also sometimes referred to as a hollow-charge or directed energy warheads.
HEAT warheads favorably recommend themselves with the fact that armor penetration does not lessen with the distance, as penetration does not depend on kinetic energy. The engagement ranges of such rounds are limited only by the probability of a hit. So, this type of ammo is especially useful for low velocity guns, anti-tank guided missiles, hand-held anti-tank mines, and rocket launchers.
Germans used shaped-charge rounds at the end of 1941, though were designed in 1938. Foster discovered shaped-charge effect in 1883. By directing the energy of an explosion by placing it in a hollow he could increase the resulting directional force by a factor of two.
See on how a HEAT projectile works.
| Anti-Fortification or Anti-Concrete Ammunition | |
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Anti-concrete ammunition is intended for the destruction of ferroconcrete, strong stone and brick buildings that are adapted to defense.
In their design, such shells are intermediate between AP and HE shells. The case of these shells as made out of high quality steel with strong sides, as the shell needs to penetrate concrete intact before exploding. The use of such ammunition is generally reserved for large caliber weapons, as its effectiveness is a direct result of a shock and an explosive force.
| Incendiary Ammunition | |
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Such ammunition is generally designed to ignite materials around it and cause damage by a secondary effect of the resulting fire. Special incendiary elements are set in the shell casing. Each element represents a metal environment filled with incendiary material such as thermit or white phosphorous. During the explosion of the shell the incendiary elements are scattered over great distance, setting the surroundings on fire and generate heat up to 3000 C°. The use of such ammunition has a strong suppression and psychological effect on enemy troops. |
| Mortar Projectile | |
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A mortar round is usually a very simple and effective weapon. The construction of one usually consists of an explosive charge, stabilizer, detonator and basic and supplemental charges.
The case is designed to provide maximum fragmentation during the explosion of the charge, which is detonated either by an impact or a proximity fuse. The stabilizer fins are mounted at the rear of the round and provide directional stability during the round's ballistic flight. Such devices are needed, as the round is fired from a low pressure, smoothbore tube. The firing occurs by the ignition of the primary and secondary charges located at the base of the round inside the stabilization package. The expending gasses escape from the holes in the tube and propel the round upward through the mortar tube.
The diversity of this weapon can be seen by the number of different types of warheads that are used in this basic package. A few examples of such are: fragmentation, fragmentation-incendiary and smoke rounds.
Basically there are two types of a nose: blunt and shape. A projectile with a blunt nose has less chance to ricochet off armor. In theory, it has less AP ability, but practically a blunt projectile can penetrate a very thick sloped armor! That is because a blunt projectile changes its trajectory when engages with an armor surfase.
| How the sharp projectile works: RT - the real armor thickness that must be penetrated (or path through) by a projectile; TAT - the tabled armor thickness (this number is shown in tables) As you can see, the RT value is significantly bigger then the TAT value. |
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| How the blunt projectile works: RT - the real armor thickness that must be penetrated (or path through) by a projectile; TAT - the tabled armor thickness (this number is shown in tables) As you can see, the RT and the TAT values are almost identical. |
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| On the scheme above there is one "strange" thing: why the blunt projectile changes it trajectory? It changes it because of blunt nose which is often covered with a tip that's made of a special materials. Ofthen there are soft metals with the big Constant of Friction. When the projectile meets with the angled armor surfase, the tip starts to hinder (to impede) the projectile. This resulting to change its trajectory so the angle between projectile's axle and the armor surface becoming ~90°. In Russian this effect names "Normalization". Of cource, blunt projectiles are inferior to sharp projectiles if used against vertical armor. |
Lets analyze one simple example. A projectile with the sharp nose engages with the King Tiger's frontal armor. Will this projectile penetrate it? Lets see:
As you can see on the picture above, we need to calculate the "l" value. From the school course of the Geometry we know that:
The thickness of the King Tiger's frontal armor is 150mm. The armor is angled at 40° to the horison, thus the engagement angle between our projectile and the armor surfase will be 50°. Thus:
Now we may take the armor penetration table and see the proper value for our projectile (for 90° of course). If it less than 235 mm our projectile won't penetrate the King Tiger's armor.
Author:
Sources: "Artillery from Alpha to Omega" encyclopaedia. Special thanks to: David Honner and Robert Livingston |