The simplest fragmentation projectiles are only capable of natural fragmentation, that is, the random scattering of fragments under the action of a high explosive. Such shells will be present in the arsenals of the warring parties for a very long time, but the demands of the time and the tastes of buyers require new, more effective ways to eliminate the enemy on the battlefield.
A certain and quite confident competition for them is fragmentation ammunition with shells of a given crushing, but in this material we will omit the details, since this is a topic for a separate article.
The first in the innovative line of "smart" are fragmentation ammunition with ready-made submunitions that provide stable characteristics of the fragmentation field. Often, simple balls are used as ready-made lethal elements - this, for example, is implemented in hand grenades and aerial bombs, which are not structurally adapted to heavy shock overloads. In the German M-DN21, with a total mass of a grenade of 221 grams, there are 2200 balls inside, each weighing 0.45 grams. Back in the middle of the last century, researchers have proven that the most effective effect on both living and material parts is a fragment weighing 0.5 g with a specific kinetic energy of about 100 J / cm2. It is difficult to imagine what difficulties doctors will face in treating multiple shrapnel wounds from such ammunition. It is worth noting that a classic projectile, when detonated, gives about 77% of fragments in the mass range of 0.1-1.0 g, the overwhelming majority of which does not reach 0.5 g. Another argument in favor of ready-made striking elements was the medical statistics of World War II indicating that the fragments weighing 0.5 g and less as the most "lethal" fraction of the striking elements - 66.6% of all wounds accounted for just such fragments. Fragments of more than 10 g, due to their rarity, caused injuries only in 6, 7% of cases. The second option for fragmentation ammunition with ready-made lethal elements is to equip them with a supporting metal shell that protects against shock overloads in the gun barrel. The flip side of this solution is the fragments of the supporting structure with noticeably worse characteristics than that of ready-made striking elements. This is an experimental 105 mm XM0125 howitzer projectile containing 7800 tungsten balls and 2 kg of explosives. The German 76-mm DM261A2 projectile for a naval automatic cannon, containing 2200 balls with a diameter of 4 mm and 580 g of explosive, also belongs to the class of fragmentation ammunition with a carrying shell. Balls as destructive elements are also not sinless - their binder (usually epoxy glue) during explosive detonation is quickly "blown out" by hot explosion products, which naturally reduces the kinetic energy of the finished fragments.
To prevent the breakthrough of gases, engineers proposed to install a thin shell (liner) between the explosives and the balls, or simply to shape the elements into hexagonal prisms, minimizing the gaps between the deadly pieces of metal.
Rod warhead design: 1 - annular explosive device; 2 - points of pairwise welding of adjacent rods; 3 - rods laid in two layers; 4 - explosive explosive charge. Source - Weapons and weapon systems. Authors: V. A. Odintsov, S. V. Ladov, D. P. Levin.
A separate phenomenon is the ready-made striking elements of missiles, which are steel rods of round or square cross-section, laid on top of the explosive charge and isolated from its destructive action by a damper. Engineers provided two options - rods welded alternately by the upper and lower ends, which, when exploded, form a continuous ring, that is, a huge single striking element, and separately laid rods, which form a circular flow of individual elements. The aim is to cover the aircraft, which the rods cut like a knife to butter, destroying the structural elements - this is how, for example, the 9M333 SAM of the Strela-10 self-propelled air defense system works. In the 2S6 "Tunguska" complex, the 9M311 missile has a combined warhead weighing 9 kg, composed of 600 mm long rods and cubic fragmentation elements weighing 2 to 3 g. The rod "cuts" the enemy aircraft, and the steel cubes cause the fuel system to ignite.
To hit targets in the upper layers of the atmosphere, or beyond, fragmentation munitions are being developed, which, when detonated, form narrow circular fields of low-velocity fragments. A kind of "network" is created for an approaching object, in which the density of fragments is high enough for guaranteed defeat. The target usually has a strategic status and has hypersonic speed, so the submunitions do not need serious acceleration to impart kinetic energy. The apotheosis of engineering is becoming promising cluster fragmentation fields, which are steel nets (fields) or folding gratings deployed by an anti-missile on the way of an approaching ballistic one. For example, Lockheed-Martin has developed an orbital interceptor with a rigid (coupled) field within the framework of the HOE (Homing Overlay Experiment) program. The length of the telescopic feather of the interceptor is 2,050 mm, each feather has five heavy ready-made striking elements. It is also proposed to integrate an additional explosive charge into the shell of such an obstacle, which is triggered when interacting with the target.
Interceptors for ballistic missiles with a "veil" field: a - constant density screen field; b - rigid (bound) field.
Source: Weapons and weapon systems. Authors - V. A. Odintsov, S. V. Ladov, D. P. Levin.
The circular propagation of fragments has one significant disadvantage - at small angles of approach to the target, some of the damaging elements go into the ground without causing significant harm. Therefore, the next step of the smarter fragmentation ammunition is to rotate to the vertical axis just before detonation. Domestic cluster 122-mm projectile MLRS "Prima" used to go to the vertical parachute, but this required sufficient time and height of deployment. High-speed projectiles for instant reversal are equipped with jet engines or rejected powder charges of ballast masses. A promising design of a feathered fragmentation projectile for the D-81 tank gun provides for a remote fuse for a propelling powder charge. Together with the sensor of the angular position of the projectile, the projectile "brains" give the command to the powder at a certain moment to explode and eject at a speed of 200 m / s two weights with a total mass of 1.2 kg, which provides an impulse of 240 N · s. As a result, the projectile turns 90 degrees over 15 meters and detonates. A circular fragmentation field is evenly "distributed" over the enemy …
The scheme of the parachute-braking turn of the cluster combat elements: 1 - ejection from the cassette; 2- shooting of the cover and exit of the parachute; 3 - the stage of the turnover; 4 - undermining. Source - Weapons and weapon systems. Authors: V. A. Odintsov, S. V. Ladov, D. P. Levin.
Fragmentation-beam projectiles are a relatively new trend in artillery tank systems, implemented in Russia in the Ainet system for the T-90S. The rangefinder, ballistic computer and automatic installer of the 3VM18 temporary (trajectory) fuse provide inductive input of the detonation parameters immediately before the projectile is fed into the barrel. Ready-made submunitions - usually miniature cylinders - are located in the nose of the projectile, separated from the explosive dampers, and provide a directed stream of debris or "beam".
Source: otvaga2004.mybb.ru.
Russian concepts of tank fragmentation-beam projectiles with head (a) and head (b) fuses: 1 - head contact assembly; 2 - head cap; 3 - lightweight aggregate; 4 - block GGE; 5 - diaphragm; 6 - shell body; 7 - explosive charge; 8 - bottom temporary fuse; 9 - optical window for entering the installation on the trajectory; 10 - stabilizer; 11 - case; 12 - trajectory contact fuse; 13 - receiver of installations; 14 - fragmentation block; 15 - plastic glass; 16 - central tube; 17 - stabilizer body; 18 - drop feathers. Source: Weapons and weapon systems. Authors: V. A. Odintsov, S. V. Ladov, D. P. Levin.
It is important that the projectile's own speed is added to the flight speed of the directed fragments, which provides high kinetic energy of the destructive elements. During detonation, the carrying body of the projectile forms a secondary circular field of fragments, allowing more efficient use of the projectile material. In the future, all domestic high-explosive shells of tank guns will be replaced by high-explosive fragmentation shells, especially since the potential enemy is already using them to the full. In Israel, this is the M329 Apam from 2009, which is capable of making six consecutive explosions on the trajectory, which leaves no chance for a tank-hazardous force in narrow city streets. The German DM11 projectile with a three-mode fuse from the weapons "studio" Rheinmetall has tungsten balls as striking elements.
DM11 projectile with a supersonic needle in the head. Source: andrei-bt.livejournal.com.
From the classic cumulative and high-explosive tank shells, the new design borrowed a supersonic nose needle, which forms a Mach cone in flight and is responsible for stabilizing the projectile on the trajectory. The Swedes from FFV are experimenting with a combined projectile "P", which belongs to a new class of cluster fragmentation-beam projectiles. In the body of the ammunition there are two missile blocks with propelling powder charges. Approaching the target, the automation sequentially fires blocks from the projectile, which, in turn, exploding, throw the striking elements. Such multi-stage attack mechanics impart a speed of about 1600 m / s to the steel 25-gram balls, which guarantees penetration of the tank roof up to 40 mm thick.
Combined projectile "R" of axial action: 1 - remote fuse; 2 - powder firecracker for removing the head cap; 3 - shell body; 4 - throwing block; 5 - expelling powder charge; 6 - detonator of a propelling unit with a retarder; 7- layer of GGE.
Source: Weapons and weapon systems. Authors: V. A. Odintsov, S. V. Ladov, D. P. Levin.
Meniscus or multi-element fragmentation ammunition of a given crushing look quite exotic. The "highlight" of the design is the shell of the projectile, treated with high pressure with the formation of shallow recesses in the form of menisci or cones with large opening angles. Got a neat idea from the engineers? When explosives are detonated, miniature "shock nuclei" are formed, being thrown at a speed of 1800-2200 m / s and piercing armor barriers up to one meniscus diameter. Reducing the opening angle to 70-90 degrees modifies the compact "impact core" to a cumulative jet, and the ammunition itself is called multi-cumulative. The category of rare ones includes ready-made striking elements of an improved aerodynamic shape, that is, swept-like with plumage and asymmetrical flat ones. They fly far, have a high lateral load and are very effective in protected manpower. However, the problem of safe throwing from high shock loads during detonation of explosives remains difficult - the striking elements are destroyed and deformed. Therefore, aerodynamic elements are thrown carefully, using a powder charge and at a speed of no more than 200 m / s.
