General purpose machine gun

A general purpose machine gun (GPMG) in concept is a compromise weapon, a machine gun intended to fill the role of either a light machine gun or medium machine gun, while at the same time being man-portable. However, performance in either role may be inferior to a weapon specifically designed for that role. In modern practice, they are air-cooled medium machine guns firing full-power rifle cartridges such as 7.62 NATO. They are generally operated from a stationary prone position from either a bipod or tripod, or mounted on a vehicle, as they are usually too powerful and heavy to be fired effectively on foot from an unsupported standing position or on the move.During the inter-war period, the Germany developed the Maschinengewehr 34, or MG 34 from scratch up as a GPMG, as opposed to an adaptation of an existing weapon, such as the MG 08/15. The MG 34 was air-cooled, belt-fed and had the ability to be mounted on a variety of fixtures and employed in several different roles. Notably, the MG 34 remained the standard co-axial weapon for German vehicles through the Second World War. The MG 34 was successful enough during use in the opening stages of the Second World War that the concept of the GPMG was adopted in many other post-WWII armies. But for its immediate successor the MG 42, which supplanted the MG 34 in Wehrmacht service, the MG 34 is easily the most versatile and effective machine gun design of the Second World War.

The modern GPMG (or "Gympy" in military slang) is a medium machine gun which operates as a support weapon. The term, which comes from the Belgian name Mitrailleuse d'Appui General or General Purpose Machineguns (GPMG), became popular for describing medium machine guns used in multiple roles. The mediums fired full power rifle caliber ammunition, but had some concessions for more extended firing and more general usage. This generally included both bipod and tripod/pintle mounting options and quick-change barrels. The first medium machine guns used as a GPMG traces back to WWI, where aircooled medium machine guns were used in many different roles, typically with larger magazine on aircraft, tanks, and ships, and in lighter configurations by infantry on bipods on tripods.

M240G general purpose machine gun

The GPMG designation (or a translation of the term) has been applied by several nations to their weapons, but they did not actually apply the concept, and others did the reverse. Overall the GPMG concept itself has not been especially successful, with lighter machine guns continuing to be used as well as heavier designs. They were successful in supplanting heavy water-cooled designs firing the same caliber, but this was mostly due to that type of weapon being rendered obsolete by modern warfare. In U.S. service, for example, the M240 could be considered a GPMG, but in practice is generally used as a tripod- or vehicle-mounted medium machine gun. The lighter M249 (firing 5.56 NATO ammunition) is the main U.S. light machine gun/squad automatic weapon, and the M2 machine gun (using the .50 BMG cartridge) is used in the heavy machine gun role.

The MG3, a direct descendant of the MG 42, is still in service with the German army and others.In the British Army, the current GPMG is the L7 and in the US Army the M240 which are both versions of the FN MAG, FN Mitrailleuse d'Appui General (general purpose machine gun). The previous US GPMG (also widely used by allied nations) was the M60 machine gun. The approximate Russian equivalent is the PKM.