During World War II, the German army continually developed new and more lethal weapons for its soldiers on the Western and Eastern Fronts. A recurring problem was the complexity and resulting tight tolerances of their equipment from the early stages of the war. In short, the Germans overengineered their weapons, making their production, maintenance, and use under adverse combat conditions difficult. A prime example of this problem is the MG 34.

The MG 34 was introduced in 1934 (hence its name) and entered service in 1936. It is generally considered the world’s first dual-purpose machine gun. With its full-power rifle cartridge, the gun could be used as a light or medium machine gun for infantry units, as an anti-aircraft gun, or as a secondary gun for armored vehicles. It was light enough to be carried by one person and had a rate of fire that was unmatched at the time of its introduction.

Most German tanks were equipped with the MG 34 Panzerlauf (tank barrel). This Panzerlauf system had no stock and could be mounted internally in the hull, coaxially in the turret, or externally on the turret. However, as mentioned above, the MG 34 required precision machining and was unreliable in mud, snow, dust, and moisture. As the war became increasingly intense, the German army needed a replacement that was easier to build and more reliable in action.

Developed and put into service in 1942, the MG 42, with its stamped metal parts, was cheaper, easier to produce, more reliable, easier to use, and arguably more lethal than the MG 34. The new weapon offered a nearly 100% increased range of 2,000 meters and a 50% increased rate of fire of 1,500 rounds per minute. For this reason, the MG 42 was nicknamed “Hitler’s Circular Saw” by Allied troops, who recognized and feared the weapon’s distinctive sound.

So why wasn’t the MG 42 used in German armored vehicles if it offered so many improvements over the MG 34? In short: science. When a bullet is fired through a barrel, friction and burning propellant heat up. In an MG 34, which fires 1,000 rounds per minute, the barrel heats up relatively quickly under continuous fire. If the barrel gets too hot, the shot group opens up, and the gun’s accuracy deteriorates. Furthermore, prolonged stress on the barrel can lead to its total failure. For these reasons, machine guns like the MG 34 typically feature a quickly replaceable barrel.

On the MG 34, the barrel is removed from the barrel cover by turning the receiver counterclockwise. The old barrel can then be removed and a new one inserted. The receiver is then turned back clockwise, and the gunner can continue firing. While this design is perfectly adequate, changing the barrel on the MG 42 is even simpler. On the MG 42, the barrel pops out of the right side of the weapon. The old barrel is replaced with a new one, and the gunner then simply snaps it back into line with the receiver. However, this was simply incompatible with existing German tank designs.

In a tank, a gunner can simply rotate the MG 34 receiver and replace the barrel if it gets too hot. However, because the rest of the gun is mounted in the hull or turret, the MG 42’s side-loading barrel swap wouldn’t work. The mount designs would have to be completely redesigned to accommodate this. Furthermore, the conditions inside a tank are far less hostile than a muddy trench on the Western Front or a snowy trench on the Eastern Front. Therefore, the MG 42’s higher tolerances were unnecessary. In cases where a machine gun was mounted outside a vehicle, such as on a turret or an open self-propelled gun, the Germans still used the MG 34 to streamline spare parts logistics and weapon maintenance.

Until the end of World War II, both the standard MG 34 and its tank-barreled versions were still produced and used by the German army. After the war, Germany developed the MG 42 into the multi-purpose MG 3 machine gun. New armored vehicles were also designed with the new gun in mind. The United States incorporated design elements of the MG 42 into the M60 machine gun, which is still used in limited versions by special forces today.

Featured image: Federal Archives