Bergmann MP18 Country Germany Type Submachine gun Manufacturer Bergmann Introduction 1916 Specifications Weight 4.18 kg (9.2 lb) Length 832 mm (32.8 in) Barrel length 200 mm (7.9 in) Cartridge 9x19mm Parabellum Action open bolt blowback Rate of fire ~500 round/min Muzzle velocity 380 m/s (1,247 ft/s) Feed system 32 detachable drum magazine TM 08 (WWI); 20 round detachable box (post-WWI)

The MP18 manufactured by Theodor Bergmann Waffenbau Abteilung was the first practical submachine gun used in combat. It was introduced in service in 1918 by the German Army during World War I as the primary weapon of the Stosstruppen, assault groups specialized in trench combat. While MP18 production ended in the 1920s, its design was the base of most of the submachine guns between 1920 and 1960. The firepower of this new class of weapons made such an impression on the Allies that the Treaty of Versailles banned further study and manufacture of such light automatic firearms.

A soundly engineered piece of equipment with near commercial grade fittings and finish, the MP18 was a heavy weapon, weighing over 5 kg (11 lb) when fully loaded. The receiver tube was very thick (3 mm), compared with later World War II submachine guns with half that thickness or less.

Though Schmeisser designed a conventional 20 round capacity \"box\" magazine for the weapon, the Testing Commission, for practical reasons, insisted that the MP18 be adapted to use the 32 round TM 08 Luger \"snail\" drum magazines that was widely used with the long barreled version of the P 08 pistol known as Artillery model.

Full scale production did not begin until early 1918. The MP18 is considered the first submachine gun to be employed as such. The MP18 primarily served in final stages of World War I in 1918, especially in the so-called Kaiserschlacht offensive. At least 5,000 MP18 were built and used during World War I, based upon observed serial number ranges of captured weapons. However, it is possible that up to 10,000 were built for the war. Though production was outlawed by the Treaty of Versailles, manufacture continued in secret into the early 1920s, as the final production total (again, based upon observed serial numbers) ended at around 35,000. The MP18 continued in use with German police forces after the end of the war.