The Sten Submachine Gun

DESCRIPTION AND OPERATION
The Mark II and Mark II S, (silenced version), was produced in larger numbers than all other versions of the Sten family of weapons, from 1942 until 1944 there were over 2,000,000 made. The Sten is a magazine fed, straight blowback weapon firing from an open bolt with a fixed firing pin. The fire selector is a cross bolt type located above and in front of the trigger guard. Marked with the letters A and R, this denotes A for automatic fire on the right end of the cross bolt and R for repetition or semiautomatic fire, on the left side. To obtain automatic fire, the bolt is pushed from the left side so the end marked A is protruding. Conversely if the A side is pushed so that the end with the R is protruding the weapon will fire semiautomatically. The Mark II fires from an open bolt utilizing a fixed firing pin. The fire selector operates the same as the Mark I having a slot to control the trip lever.

The receiver is a tubular type, with a sheet metal trigger housing and buttstock of either tubular or skeletal formed metal. The most common butt stock was the tubular type, fitted with a sheet metal filler to form a pistol grip, although it is not uncommon to find them with a formed skeletal pistol grip.

The barrel may be either two or six groove and is fitted to the barrel jacket by a flanged sleeve fitted over the barrel and secured by a pin. The barrel jacket attached to the flanged sleeve is threaded at the rear for attachment to the receiver. This jacket is held in the receiver by a spring loaded plunger on the magazine housing.