December 4, 2008
|MG 42||MG 3|
|Weigth||11,6 kg (gun) + 20,5 kg (Lafette 42 trpod)||10,5 (gun) + various tripods|
|Length||1219 mm||1225 mm|
|Length of barrel||533 mm||565 mm|
|Rate of fire||1200 – 1500 rounds per minute||700-800 or 1100-1200 rounds per mniute|
With adoption of the MG 34 machine gun the Wehrmacht had the weapon that was envisaged some 20 years before, and the MG 34 bears the distinction of being the first practical universal (or general purpose) machine gun. While the MG 34 was good and practical, it was certainly not ideal. German experts wanted their machine guns to fire faster, while being simpler and less costly. A high rate of fire was desirable both for AA applications and for surprise flanking fire against targets moving through the battlefield. As early as 1937 HWaA issued a request for the next new universal machine gun,and three companies received development contracts – Johannes Grossfuss AG, Stubgen AG and Rheinmetall-Borsig AG. In 1939 a commission selected the Grossfuss-made MG 39 prototype for further development. Designed by engineer Gruner (often wrongfully referred to as Grunow) and small arms designer Horn, new weapon, in accordance with HWaA request, had a stamped steel construction, combined with locked breech, short recoil action. Initial trials suggested that the Grossfuss MG needed further development, and in late 1941 a small batch (about 1500 pieces) of improved guns was manufactured for troop trials as the MG 39/41.
The new machine gun, while being made to lower standards of fit and finish, proved to be quite functional and reliable (a feature that the much more “refined” MG 34 lacked, especially in the mud and snow of the Russian front). Subsequently, it was officially adopted as the MG 42, and production commenced later the same year.
In general terms, the MG 42 was a great success. It fulfilled the roles of a light machine gun on a bipod, a medium machine gun (on a newly developed Lafette 42 tripod), and an anti-aircraft machine gun, mounted in single and twin installations, ground and vehicle-mounted. It was relatively inexpensive to make and required less raw materials than the MG 34, and it was simple to maintain and use. On the minus side, it had a somewhat excessive rate of fire, usually quoted as 1200 rounds per minute, although German WW2 era manuals listed it as 1500 rounds per minute (25 rounds per second). This rate of fire resulted in excessive consumption of ammunition and rapid overheating. While the extremely rapid barrel change procedure allowed for sustained fire, the resulting accuracy left something to be desired; excessive vibration from recoil, combined with a short sight radius, resulted in degraded long range accuracy compared with earlier MG 34 and, especially, the heavy MG 08 Maxim guns. Nonetheless the MG 42 was an impressive and fearsome weapon, known among Allied soldiers as “Hitler’s saw”, for the sound of the firing which resembled the sound of a giant mechanical saw.
After the WW2 this weapon, unlike other wartime designs, lived on, as in 1958, the FRG (West Germany) re-instituted its official armed force, known as the Bundeswehr. Since the core of the Bundeswehr was formed of WW2 veterans, it was logical to adopt weapons which were already proven and familiar to the troops; and the MG 42 was one of such weapons. It was, obviously, chambered for a ‘non-NATO’ cartridge, but this was only a minor issue, as the 7.62×51 NATO and 7.92×57 Mauser shared the same cartridge base diameter, and were somewhat similar in ballistics. The real problem, however, was that Germany had lost most manufacturing facilities for the MG 42, so the newly reestablished Rheinmetall concern had to install production facilities from the ground up. The production documentation for original MG 42 machine guns was obtained from Grossfuss company and transferred to Rheinmetall (German government had to pay significant royalties to Johannes Grossfuns for manufacturing rights). Since the preparation for manufacture took some time, the FRG purchased some ex-Wehrmacht MG 42 weapons from other countries. Those guns were converted to 7.62 NATO by Rheinmetall and officially designated MG 2. The newly produced MG 1 guns went through a number of modifications, which resulted in the definitive MG 3 version, which still is rather close in design to the war-time MG 42, although made to much higher standards of fit and finish. The simplicity, low manufacturing cost and high effectiveness of the MG 3 attracted several other countries, which either bought the guns from Rheinmetall (such as Denmark), or obtained manufacturing licenses and build (or at least have built in the past) the same guns domestically (such as Italy, Iran, Turkey, Pakistan and Yugoslavia). In total, at least twenty armies have used or still are using the MG 3 and its versions. It must be noted that in some countries these guns were used under their “commercial” Rheinmetall designation MG 42/59.
The MG 42 is a short-recoil operated, air cooled, belt fed weapon which fires from an open bolt. The barrel is quick-removable, and can be replaced in less than six seconds by a properly trained crew, although an asbestos glove is required to remove the hot barrel. The action of the weapon is operated by the recoil of the locked barrel, assisted by a muzzle booster which uses pressure from the muzzle blast to increase the recoil impulse. Locking is achieved by a pair of rollers, which are forced outwards from the sides of the bolt head to engage cuts in the barrel extension. Locking (outward) movement of the rollers is controlled by the wedge-shaped front part of the bolt body; unlocking (inward) movement of the rollers by the cams made in the receiver. This is a simple and solid system which minimizes the length of parts that are under stress upon discharge, and also minimizes the strain on the receiver. On MG 3 machine guns, two types of bolts are available, with standard weight (about 650 gram) for fast rate of fire and with heavy weight (about 900 gram) for slow rate of fire. It must be noted that those bolts also are used along with different return springs.
The receiver and barrel jacket are made in one unit, and formed from a sheet of rolled steel, cut to shape by pressing and stamping, and then welded and pinned to form a gun housing of generally rectangular cross-section. The front part of the housing serves as a barrel jacket and has a number of oval cooling slots at all sides except the right. The right side of the jacket has one long slot which is used to remove the barrel. The barrel is held in place by a hinged lock, located at the rear of the opening in the right side of the jacket. To remove the barrel, the operator must first lock the bolt in the open position (cock the weapon), and then turn the barrel lock to the right and forward. This will release the barrel and bring its breech area out of the jacket, so it can be grabbed (using the issued asbestos glove or other heat insulation means if the barrel is hot) and pulled back and out of the jacket. The new barrel is then inserted all the way forward and lock then is snapped into place, bringing the barrel into alignment with the action.
The gun is fed using belts only. Feed direction is from the left to right; the feed is of the one-stage, push-through type. The belt is same as for the MG 34, with steel links with open pockets, assembled into non-disintegrating 50-round lengths. The same MG 34 type “Gurttrommel” 50-round drum-type belt containers can be used with the MG 42, and a new type of lightweight plastic 50-round belt container was developed in West Germany by HK and is now issued with MG 3 guns. The belt feed is operated by the reciprocating bolt which has a roller at the top of its body. This roller engages the cam track in the oscillating lever, located in the top-opening feed cover. The lever operates the belt pawls in two steps, on both opening and closing movement of the bolt, resulting in a smooth and positive feed. This two-step belt traction is particularly useful because the high rate of fire results in high-speed belt movement, and this system reduces the strain put on both the feed unit and belt links. Current production MG 3 guns can fire either non-desintegrating or desintegrating belts.
The trigger unit is of relatively simple design, and permits for automatic fire only. The manual safety is of the cross-bolt, push button type, located at the top of the pistol grip. The charging handle is located at the right side of the receiver, and is separated from the bolt group (it does not move when gun is fired). Each MG 42 was issued with an integral, adjustable bipod attached near the muzzle; MG 3 guns may have two points for bipod attachment, one near muzzle and another near the center of the gun. In the medium role, the MG 42 was used from the Lafette 42, a complicated foldable tripod with buffered cradle. A wide number of tripods is available for MG 3 guns, as produced in several countries.
The standard sights are open, fully adjustable, and mounted on folding bases. The universal tripod has provisions for mounting telescopic sights for long range and indirect fire missions.
June 19, 2008
The Puma is a German infantry fighting vehicle, currently in the pre-production stage. It will replace the aging Marder IFVs, from 2010 through 2020. Governing company is PSM Projekt System Management, a joint venture of Krauss-Maffei Wegmann and Rheinmetall Landsysteme. The Puma is one of the best-protected IFVs, while still having a high power/weight ratio.
The Puma (formerly also named Igel and Panther) started as a follow-up project to the German mid-90s “NGP” project (Neue Gepanzerte Plattformen, “New Armored Platforms”). Its aim was to collect ideas for a common base vehicle that could be used for a variety of tasks including that of the APC, IFV, air defense and replacing/amending the MBT in the frontline combat role. The NGP project was ended in 2001.
The lessons learned were incorporated into the new tactical concept named neuer Schützenpanzer (“new IFV”) in 1998. In 2002, the German army (Heer) placed an order for the delivery of five pre-production vehicles and their logistics and training services at the end of 2004. On November 8th 2007 a budget of €3 billion to acquire 405 Pumas was agreed upon.
Other nations pursue similar developments emphasizing commonality, modularity and rapid deployability based on a comparable doctrine which was also a subject of discussion within NATO. Examples of these are the American FCS vehicles, the British FRES and the German-Dutch Boxer MRAV.
The primary armament is a Rheinmetall 30 mm MK 30-2/ABM (Air Burst Munitions) autocannon, which has a rate of fire of 200 rounds per minute and an effective range of 3000 m. There currently are two ammunition types, directly available because the autocannon features a dual ammunition feed. One is a sub-calibre, fin-stabilised APFSDS-T (T for tracer), designed with high penetration capabilities, mainly for use against medium armoured vehicles. The second is a full-calibre, multi-purpose, Kinetic Energy-Timed Fuse (KETF) munition, designed with the air burst capability (depending on the fuse setting) of ejecting a cone of sub-munitions. Both ammunitions can be chosen differently from shot to shot as the weapon fires from an open bolt, that means no cartridge is inserted until the trigger is used. The ammunition capacity is 400 rounds; 200 ready to fire and 200 in storage.
While some may deem the 30 x 173 mm calibre to be too weak for future conflicts, it is necessary to say that the small caliber (for example in comparison to the Bofors 40 mm gun mounted on the CV9040) offers major advantages because of a much lower ammunition size and -weight and the large number of rounds ready to fire (the CV9040 offers only 24 shots per magazine). Ultimately, the usefulness also depends on the tactical doctrine the vehicle is used according to in combat.
The secondary armament is a coaxially mounted 5.56 mm HK MG4 machine gun with an approximate rate of fire at 850 rounds per minute and an effective range of 1000 m. The ammunition capacity is 2000 rounds; 1000 ready to fire and 1000 in storage. While this again is a smaller weapon than the western-standard of using a 7.62 mm caliber MG as secondary armament and may lack power in certain situations, it again offers advantages because it has a higher practical ROF and the crew can use the ammunition in their individual firearms as well. In situations where the lower penetration of the 5.56 mm rounds is an issue, the high ammunition load of the main gun enables the vehicle crew to use one or two main gun rounds instead. Nevertheless, the gun housing can host the 7,62 mm MG3 also.
To combat main battle tanks and infrastructure targets such as bunkers, the German Puma vehicles will be equipped with a turret-mounted EuroSpike Spike LR missile launcher.
In addition to the usual smoke-grenade launchers with 8 shots, there is a 6-shot 76 mm launcher at the back of the vehicle for close-in defence. The main back door can be opened halfway and enables two of the passengers to scout and shoot from moderate protection.
From the ground up the Puma was designed in a way to easily accommodate additional armor. It was initially planned to offer three protection classes which are wholly or in parts interchangeable. The protection class A is the basic vehicle, at 31.5 tons combat-ready weight air transportable in the A400M. Protection class C consists of two large side panels that cover almost the whole flanks of the vehicle and act as skirts to the tracks, a near-complete turret cover and armor plates for most of the vehicle’s roof. The side panels are a mix of composite and spaced armor. It adds about 9 metric tons to the gross weight. Originally, there was also a protection class B designed for transport on railway. However, it became obvious that class C lies well within the weight and dimension limits for train/ship transportation, thus the whole class B was scrapped.
According to this concept, a group of 4 A400M aircraft could fly 3 class A Pumas into a theatre, with the fourth airplane transporting the class C armor kits and simple lifting equipment. Subsequently, the Pumas could be ready in armor class C within a short time.
The basic armour can resist direct hits from 14.5mm Russian rounds, the most powerful HMG cartridge in common use today (and up to twice as powerful as the western de facto standard .50 BMG cartridge) and is said to defeat simple hollow charge warheads. The front armour is at least able to withstand 30mm AP projectiles. In protection class C, the flanks of the Puma are up-armored to about the same level of protection as is the front, while the roof armor is increasingly able to withstand artillery or mortar bomblets.
The whole vehicle is protected against heavy blast mines (up to 10kg) and projectile charges from below while still retaining 450mm ground clearance. Almost all equipment within the cabin, including the seats, has no direct contact the floor, which also adds to crew and technical safety. All cabin roof hatches are of the side-slide type which make them easier to open manually, even when those hatches are obstructed by debris. The exhausts are mixed with fresh air and vented at the rear left side. Together with a special IR-suppressing paint, this aims at reducing the thermal signature of the IFV.
Another crew safety measure is that the main fuel tanks are placed outside of the vehicle hull itself, mounted heavily armored within the running gear carriers. While this may pose a higher penetration risk to the tanks, it is unlikely that both tanks will be penetrated at the same time, enabling the vehicle to retreat to a safer position in case of a breach. There is also a collector tank within the vehicle to secure steady fuel flow which may act as a reserve tank in case of a double tank breach.
Type Infantry fighting vehicle
Place of origin Germany
Weight 31.5 tonne, 43 tonne maximum weight with add-on armor
Length 7.4 m
Width 3.7 m (uparmored)
Height 3.1 m
Crew 3 + 6
Ground clearance 450 mm
Fording depth 1.5 m
armament 30 mm MK30-2/ABM autocannon; 200 rounds/min rapid shot, 700 rounds/min fully automatic
armament 5.56 mm HK MG4 machine gun; Spike LR anti-tank guided missile; 76 mm grenade launcher; Smoke-grenade launchers
Engine MTU V10 892 diesel
800 kW (1073 bhp)
Power/weight 25,4 kW/tonne
range 600 km
Speed 70 km/h