July 2004
 

Teeth and claws for the Puma

New automatic cannon and ammunition planned

Germany's two big tank makers, Rheinmetall Landsysteme and Krauss-Maffei Wegmann, are currently working together to develop the Puma, a new infantry fighting vehicle for the Bundeswehr. The German Army's Armour Branch is expected to take delivery of the first of the new vehicles in 2006. With a procurement bill currently being prepared for passage in the German Parliament, the two companies are confident that a contract for full-scale production will be awarded this autumn.
 

Barely off the drawing board, Germany's new Puma infantry fighting vehicle – airportable, highly mobile, modularly armoured and heavily armed – has already taken its place among the most advanced systems of its kind, worldwide. Armed and armoured specifically for rapid deployment missions, the Puma definitely has what it takes to dominate the modern battlefield. For the vehicle's main armament, the Armoured Branch has opted for a new MK 30-2 automatic cannon made by Rheinmetall Waffe Munition GmbH, which will fire high-performance Air Burst Ammunition, developed and produced by the Swiss company Oerlikon Contraves Pyrotec AG. Like RWM, Oerlikon Contraves Pyrotec AG is a subsidiary of Rheinmetall DeTec AG.

The Puma IFV, whose main armament and ammunition had to be modified to match the altered threat spectrum, represents the ultimate in battlefield lethality and survivability. In order to accomplish its full range of missions, the Puma weapon system will have to be able to cope with a multiplicity of threats from the ground and the air. In particular, the threat to armoured vehicles from the air will increase significantly over the next few years. Today, attack drones, smart bombs, better antitank weapons and airmobile assets mean that technologically advanced opponents are able to break up assaults by mechanized infantry elements much more effectively.
 

When it comes to opponents who are not as well equipped or as technologically advanced, quite different combat criteria come to the fore. Such forces prefer to fight in places that make them hard to observe or engage effectively at a safe standoff. By exploiting existing infrastructure and buildings (Urban Warfare/MOUT), and engaging in decentralized combat operations with concealed movements, light forces are able to confront a technologically superior, armoured attacker. Furthermore, an inferior force will seek to draw the enemy into a running battle in broken terrain, wooded areas and – most especially – heavily built-up towns and cities. In the view of the German Army, armoured formations in the future will have to become better at conducting operations with IFVs in difficult terrain and built-up areas.

In spite of the altered military requirements profile, the Armour Branch still constitutes an essential component of the German Army's offensive capability. In any modern army, armour has the task of seizing and maintaining the initiative in mobile operations, operating day and night in a matrix of fires, barriers and movement, acting in close coordination with other ground and airmobile elements. In order to ensure a high degree of thrust, lethality, survivability and sustainability, armoured operations must be highly mobile in nature. To meet this fundamental military requirement, the German Army of the future will need high-performance, extremely hard-hitting, highly mobile infantry fighting vehicles that will enable its mechanized infantry units to overcome even numerically superior forces on the battlefield.
 

New automatic cannon and ammunition

The Armour Branch's decision to opt for the already available MK 30-2 automatic cannon from Rheinmetall Waffe Munition (RWM) and "ABM" ammunition (made by Oerlikon Contraves Pyrotec) for the Puma infantry fighting vehicle, will simplify the design of the new IFV, as well as reducing the system's ultimate price tag and obviating the need to develop new main armament and ammunition from scratch. This decision will not only make the system cheaper for the German government, but more quickly available as well.
 

The newly selected 30 mm automatic cannon from RWM, coupled with timer-controlled, ABM ammunition, represents an extremely effective, threat-oriented system component, providing German armoured units with the firepower necessary to deal with a wide variety of targets. The 30 mm cannon and the accompanying ammunition both feature a very high level of technical and ballistic functionality, constituting the key elements of the Puma's new weaponry concept. The MK 30-2 automatic cannon has already been integrated into Austria's Ulan IFV and Spain's Pizarro system, and is now being mooted as the main armament for the Greek Army's Kentaurus ("centaur") infantry fighting vehicle.
 

The MK 30-2 automatic cannon

As the standard calibre for automatic cannons, 30 mm has already won numerous adherents worldwide, who point to its long maximum effective range and high rate of fire. Developed and manufactured by Rheinmetall Waffe Munition, the MK 30-2 automatic cannon fires standard 30 mm x 173 mm ammunition and is capable of a high rate of fire, meaning that it was practically foreordained for use in infantry fighting vehicles.

Its long maximum effective range and great accuracy make it possible to open fire on stationary and moving targets alike, which would be impossible to hit either with rifle fire, heavy .50-calibre (12.7 mm) machineguns or smaller-calibre automatic cannon. The MK 30-2 automatic cannon – coupled with sub-calibre armour-piercing fin-stabilised discarding sabot with tracer (APFSDS-T) or Air Burst Munition/Kinetic Energy Time Fuze (ABM/KETF) rounds – can engage armoured vehicles at distances of up to 3,000 metres. Helicopter gunships and drones can also be effectively engaged with the gas-operated MK 30-2 automatic cannon firing suitable ammunition.
 

Design features

Simple handling, high reliability and an uncomplicated design characterize the MK 30-2. Its principle assemblies are the barrel, weapon housing, ammunition feeding device and recoil mechanism. The MK 30-2 is a conventional high rate of fire automatic cannon capable of firing single rounds or burst fire (of up to 200 rounds per minute); it can also deliver sustained fire. Equipped with an electronic ignition coil, the maximum rate of fire of the 3,307 mm-long MK 30-2 is approximately 700 rounds per minute, according to the manufacturer. With two-belt feed, the MK 30-2 weighs 173 kg.

To ensure high firepower, maximum ballistic performance and a long service life, the drawn inner barrel of the MK 30-2 is chrome plated. Also chrome plated is the entire ammunition storage magazine. The drawn section of the 30 mm barrel is just 2,273 mm long.
 

A special design feature of the 30 mm automatic cannon is its two-belt feed system, which enables two different types of ammunition to be fired. In combat, the gunner is free to select either of the two ammunition types, e.g. KE or ABM ammunition (for engaging armoured targets). The 30 mm automatic cannon is on a floating mount. When a round is fired, a return damper significantly reduces the recoil forces during barrel runout. When a single round is fired, the recoil forces amount to 18 kN; with a short burst of fire, 16 kN.

The MK 30-2's two-belt feed system enables the gunner to switch ammunition types during a firefight to match the type of target he is engaging. The automatic cannon can be fired either electrically or manually. Thus, if the power fails or the vehicle is crippled, the weapon can still be operated. The manufacturer has seen to it that the weapon can be linked to a computer-supported fire control system. Because it is a breech-type weapon, the MK 30-2 reaches its top rate of fire after firing just a single round. Ammunition is supplied to the automatic cannon via the two-belt feed system mentioned above. Rigid locking of the breech with support flaps underneath and forced guidance of the striking pin make the weapon extremely safe to operate.
 

Switching ammunition

If a second ammunition type is taken along, the following possibilities open up for the gunner: to select one of the two ammunition types on board, or the safety position, the feed assembly is moved into a defined position. The desired type of ammunition is immediately available at all times, without a single "miss". This is a huge tactical advantage when engaging fast-moving targets.

The MK 30-2 is ready to fire when the breech is held in the rearmost position by the trigger and the ammunition is in the feed position. Prior to firing, the gunner selects the desired firing mode (single shot, short burst or sustained fire), and the of type ammunition. After actuation of the firing lever, the trigger of the MK 30-2 is released and firing can commence.
 

APFSDS-T ammunition

Because the Puma will have to be able to deal with a broad array of targets on the battlefield, ranging from armoured vehicles to reinforced field fortifications, two different types of ammunition have been selected: the armour-piercing, programmable ABM/KETF round, and the armour-piercing 30 mm x 173 ammunition/PMC287 APFSDS-T, which enables armoured targets with monoblock and spaced armour to be successfully engaged.

Developed and manufactured by Oerlikon Contraves Pyrotec, the APFSDS-T round represents a tried and tested sub-calibre cartridge technology. The projectile features a sub-calibre heavy metal flechette made of tungsten, encased in plastic in an injection moulding process, during which the driving band is integrated. This prevents the problem of driving band slippage (which can be caused by barrel erosion or environmental factors) from occurring.
 

APFSDS-T Ammunition (30 mm x 173)

After ignition, the projectile leaves the barrel of the 3 0mm weapon at full spin. In the process, the sabot is discarded as soon as it leaves the muzzle. Neither the trajectory of the 235-gram projectile nor its ballistic characteristics are impaired. The projectile covers 1,000 metres in 0.75 seconds, and 2,000 metres in just 1.56 seconds. The muzzle velocity of the projectile is 1,405 metres per second. It is capable of penetrating 63 mm thick steel armour. Even at very flat impact angles, such as a plate angle of 60 degrees (Nato), the projectile will penetrate an armoured target. The same is true of add-on armour. The projectile can even penetrate the armour of an M60 main battle tank at a range of 1,500 metres. 30 mm x 173 /PMC 287 ammunition is suitable for engaging infantry fighting vehicles and light tanks.
 

ABM/KETF ammunition

This is a completely new type of ammunition for armed forces, enabling a wide spectrum of ground and even air targets to be successfully engaged. Likewise developed by Oerlikon Contraves Pyrotec, this projectile will add greatly to the battlefield lethality and firepower of the Puma IFV, making it superior to any other German system of its kind. Prompted by the high ballistic performance parameters of the programmable ABM/KETF round, and the speed with which it could be made available to the troops, the German procurement authorities opted to buy the new ammunition type last year.

The ABM/KETF round is based on Nato-qualified Ahead technology. The projectile contains a programmable fuse, which is furnished with data from the fire control unit via an electronic ignition programmer coil at the muzzle. In this way, the projectile receives all the relevant data it needs for taking out an air or ground target. Transmitted in the space of 25 microseconds, the data are electronically received and stored by a programming unit located in the tail assembly of the projectile. ABM/KETF projectiles are hardened against all electronic countermeasures.

Contained in the nose of the ABM round is the payload/warhead. This consists of 162 cylindrical subprojectiles made of tungsten heavy metal, each weighing 1.24 grams. Upon reaching the target, these are explosively released by a 0.5 gram-ejection charge, which forces them forward. The presence of magnesium in the ABM/KETF round, which results in a readily visible flash of light when the sub-projectiles are ejected, makes it possible for the gunner to observe the process. Circularly arrayed in superimposed rows of five, the tungsten projectiles of the ABM/KETF are spin-stabilized, and form a lethal cone, significantly increasing the probability of a hit, particularly at long ranges.

The impact of the 30 mm x 175 ammunition can be influenced by altering the distance at which the sub-projectiles are released ahead of the target, as well as by varying the number of rounds fired. The technical option of detonating the projectiles in different ways in the vicinity of the target also boosts the likelihood of a hit. In the event of a helicopter gunship attack, for example, the rounds can be programmed to explode sequentially along the flight path of the target, distributing their submunition charges over several hundred metres. Flying into a swarm of sub-projectiles, the attacking helicopter is forced to abort the mission or risk destruction. Even incoming missiles can be successfully warded off with ABM rounds detonating in the air around them.
 

ABM ammunition

Moreover, the ammunition can be programmed to detonate at a specific height and distance from the target, subjecting it to heavy fragment impact. Thanks to this new ammunition, hardened field fortifications and antitank positions can be successfully engaged at ranges of up to 2,500 metres for the first time. The fragmentation effects of the ABM/KETF are such that even elaborately prepared positions can be out of action indefinitely. In addition, this ammunition can also be employed against IFVs and light armoured vehicles. The fragmentation effects of ten or so rounds is sufficient to destroy an IFV's optical systems, e.g. its night observation equipment or periscope.

A diverse family of ammunition is available for exploiting the great operational potential of this weapon. These range from practice rounds to both classic and newly developed service ammunition, assuring the future growth potential of this highly successful weapon.

Specifically, these include the:

• TP/TP-T full-calibre practice ammunition with tracer;
• TPFDS-T sub-calibre practice ammunition with reduced impact behaviour;
• HEI/SD-T sub-calibre with mechanical nose fuse/self-destruct element and tracer for use against light armoured ground and air targets;
• MP-T is a reasonably priced multi-purpose equivalent of HEI ammunition with a pyrotechnic nose fuse for use against light and semi-hard targets. A variant of this round, MPHC-T, offers enhanced penetrating power;
• SAPHEI-T is full-calibre multi-purpose ammunition with a mechanical base fuse and tracer. Used against semi-hard targets, it achieves excellent penetration results, even with a flat impact;
• APDS-T is a sub-calibre, armour-piercing, discarding sabot round with tracer, for use against hard targets;
• APFSDS-T is a sub-calibre, fin-stabilised ammunition with tracer. Designed to prevent barrel erosion, it is highly effective against monoblock and multi-layer armour at extreme impact angles;
• FAPDS-T is an armour-piercing, sub-calibre ammunition without a fuse; its explosive charge has an enhanced secondary effect, and is highly effective in defeating homogenous and composite armour;
• ABM airburst ammunition with sub-projectiles is designed for use against hard, semi-hard and surface targets. Each round contains 135 sub-projectiles, which are programmed to eject at a specific distance from the target. Programming takes place at the muzzle brake. The projectile's flight time, which is derived from the muzzle velocity and the distance to the target, is programmed into the ammunition as it leaves the barrel. Disintegration of the round and ejection of the sub-projectiles take place in accordance with the computed and entered values. The time signal is not susceptible to electronic countermeasures.

MK 30-2 with ABM ammunition is destined to be the main armament of the new Puma

Germany's new infantry fighting vehicle will be armed with the MK 30-2 automatic cannon, enhanced with ABM ammunition technology. The ABM projectile contains a programmable timer fuse. After measuring the current velocity, the timer setting is calculated and each individual round is inductively programmed at the muzzle of the barrel. The payload of the ABM consists of cylindrical heavy metal sub-projectiles, which are released by a small explosive charge. Because the standoff to the target at the point of ejection can be varied, the ABM is capable of destroying a broad of spectrum of modern battlefield targets, including – first and foremost – infantry fighting vehicles, fortified antitank positions, helicopters and dismounted troops.
 

This article originally appeared in the June 2004 issue of "Behörden Spiegel".