Sten
The STEN gun was a British submachine gun from World War II, notable for it simple design and low cost of production, being made from only 47 different parts. It was even cheaper and more spartan than the German MP38/MP40, the previous benchmark in the field of mass-produced infantry weapons. The simplest version of the STEN gun, the Mark III, required only five man-hours to produce. It was distinctive for its bare appearance (just a pipe with a metal loop for a stock), and its horizontally-orientated magazine. The name STEN is an acronym, deriving from the names of the weapon's chief designers, Major Reginald Sheperd and Harold Turpin, with the EN derived from "ENfield", after Enfield Lock, the location of the Royal Small Arms Factory.
The STEN gun was chambered for the 9 x 19 mm Parabellum pistol cartridge, in part so as to make use of captured German ammunition supplies. The STEN was small and could be stripped down into a set of innocuous components, and was therefore particularly suited to partisan operations on the continent; guerilla fighters in western and eastern Europe became adept at repairing, modifying and eventually scratch-building clones of the STEN (over 2000 STENs and about 500 of similar Blyskawica SMGs were manufactured in an occupied Poland). It was often disparaged by soldiers for inaccuracy, due to very basic sights, and stoppages due to the design of its magazine. Furthermore, it was prone to accidental discharge if dropped or knocked. The design was continually improved throughout the war, and remained an issue weapon in the UK until well into the 1960s, after which it was replaced with the more conventional Sterling SMG.
The STEN was a panic measure, designed at a time when Britain was facing imminent danger of being invaded by the Nazis. Prior to 1941 the British army had purchased Thompson submachine guns from America, but these were expensive and supplies were vulnerable to U-Boat attack. In order to rapidly equip a sufficient fighting force to counter the German threat, the Enfield armory was commissioned to produce a radically cheaper alternative.
STEN guns were produced in five basic marks, although the fourth was never issued. The rare Mark I had a conical flash hider and a rudimentary forward pistol grip; the Mark II (pictured above) was the most prolific, at 2 million units, with the even-simpler Mark III following closely behind. The Mark IV was a pistol-sized version which did not progress beyond the prototype stage, whilst the Mark V (which was used in Normandy and at Arnhem) included wooden pistol grips, a stock, and a bayonet mount. There were also modifications Mark IIS and Mark VI which incorporated an integral sound silencer. All combined, approximately 4.5 million Stens were produced during the war, many of which were airlifted by the crate to resistance fighters throughout occupied Europe. Due to their slim profile, and ease of dismantlement, they were good for concealment and guerilla war. Unfortunately, the most famous engagment involving a STEN - the assasination of Reinhard Heydrich - was almost thwarted when the STEN jammed, its flimsy magazine being prone to warping, especially as it was used as a forward handgrip.
As with the M1 Carbine, the STEN attracted affection and loathing in equal measure, its distinctively ugly design appealing to fans of the underdog, whilst its questionable reliability and durability did not endear it to front-line troops. Nonetheless the Sten saw continued use even after the economic crunch of WWII was over, replacing the Royal Navy's Lanchester submachine guns on into the 1960s. Specialized versions of the Sten were used by British commandos in Korea, due to its very low weight and bulk.
STENs were so cheap and plentiful that, despite the generally high cost of WWII era collectibles, deactivated STEN guns can be had usually for less than £200.
An interesting tidbit; George VI carried a Sten Mk.II in his car for self-defence purposes in case of a paratrooper attack. This gun can been seen in the Imperial War Museum.
