MACHINE CARBINE, 9MM STEN, MARK 2
The STEN gun was a product of wartime expediency and production methods, born through the necessity of an island nation with limited resources.

At the beginning of World War II, Great Britain had bought many Thompson sub machine guns from the USA, via the Lend-Lease agreement but the supply was severely threatened by U-Boat attacks on the ships conveying these supplies to Britain.

British authorities decided to produce a native design, to enable a constant supply. The Lanchester design, based on the German MP28, was chosen in 1940 but was still
too production intensive to create the numbers of sub-machine guns needed.

In 1941, a new design was tried and eventually accepted. Its name, ‘STEN’, came from the initials of the designers - R. V. Shepard & H.J. Turpin and Enfield, the manufacturers.

It was still a well made gun in its Mk.1 form and the more basic Mk. 2 model simplified production further. The Mk. 2 model is the most well known model of Sten and was supplied to resistance groups, as well as Allied forces.

The operation of the Sten is simply the blowback principle, with a stick magazine. Selective fire capability is contained within the trigger mechanism.
The Sten was copied by other nations well after World War II had ended and just goes to prove that its simple but effective design could perform admirably in combat.

OPERATION
FEED 
CALIBRE
CYCLIC  RATE OF FIRE
LENGTH  (OVERALL)
BARREL  LENGTH
WEIGHT  UNLOADED 
MUZZLE  VELOCITY

GAS  BLOWBACK
32  ROUND DETACHABLE BOX MAGAZINE
9mm
550  rpm
30.0  inches / 762mm
7.75  inches / 1966mm
6lb  8oz / 2.95kg
1250  fps / 381 mps
 

MACHINE CARBINE, 9MM STEN, MARK  5
The early STEN was never really popular with British troops mainly because its single feed magazine gave so many jams. In 1944 an attempt to overcome the opposition to the Sten was made by producing a better version with a more robust and expensive appearance. Rather more care was taken in machining and assembly and the finish was improved, a wooden stock and pistol grip were fitted and a foresight from the Number 4 Rifle was adapted to the barrel.  The No4 rifle bayonet could be fitted to the muzzle and the butt plate had a trap for cleaning materials.

Entered British Army Service March 1944

OPERATION
FEED 
CALIBRE
CYCLIC  RATE OF FIRE
LENGTH  (OVERALL)
BARREL  LENGTH
WEIGHT  UNLOADED 
MUZZLE  VELOCITY

GAS  BLOWBACK
32  ROUND DETACHABLE BOX MAGAZINE
9mm
600  rpm
30.0  inches / 762mm
7.75  inches / 1966mm
8lb  9oz / 3.86kg
1250  fps / 381 mps
 

REFERENCES

1. MILITARY SMALL ARMS OF THE 20TH CENTURY 4TH EDITION
By Ian Hogg & John Weeks 1981 DBI BOOKS ISBN 0-910676-28-3

2. MODERN SMALL ARMS
By Major Frederick Myatt MC 1979 SALAMANDER BOOKS ISBN
0-86101-024-8