STEN Mk. II Submachine Gun

The STEN or Sten Gun is a British-made submachine gun. It was designed in 1940 and used by the Allied armies during World War II and in the post-war period. The designers were Harold John Turpin and Major Reginald Vernon Shepherd. The name Sten is an abbreviation of their names Shepherd and Harold Turpin and EN for the Enfield factory where the submachine guns were manufactured.

The British Army at the start of World War II was almost out of submachine guns, so in 1940 a large order was placed for American-made Thompson submachine guns. At the same time, a home-made design was being developed at the State Arsenal in Enfield. The designers Reginald V. Shepperd and Harold J. Turpin developed a simple and inexpensive submachine gun with a minimum of machined parts, using stamping and welding. It was adopted into service in 1941 as the Machine Carbine STEN Mk I. The Sten was designed with as few parts as possible. The simplest versions had 47 parts. The magazine, which had a capacity of 32 rounds, retracted into the side from the left side. It used 9 mm Luger pistol ammunition.