The STEN is the name for a family of submachine guns designed by the British and used in World War II. They are known for having a simple design and a low production cost. The name Sten is an acronym, based on the names of the designers of the gun: S for Shepherd (Major Reginald V. Shepherd), T for Turpin (Harold Turpin), and EN for Enfield (the manufacturer of the gun).
History and DesignEdit
Sten guns were created out of necessity, because England was faced with invasion by the German Army, and they had a very small amount of suplies. The Thompson submachine guns suplied by America were not enough, especially after America entered the war and needed most of them for their own troops. Thus Enfield was given the task to create a new submachine gun for England.
The Sten was designed to be cheap and easy to build, and the manufacturing required for it's creation was minimal. The production could be mainly preformed at small workshops with whatever metal the shops happened to have at the time.
The Sten was a blowback-operated submachine gun firing from an open bolt with a fixed firing pin on the face of the bolt. This means the bolt remains to the rear when the weapon is cocked, and on pulling the trigger the bolt flies forward under spring pressure, stripping the round from the magazine, chambering it and firing the weapon all in the same movement. There is no breech locking mechanism, the rearward movement of the bolt caused by the recoil impulse is arrested only by the mainspring and the bolt's inertia. The appearance of the gun is basically just a pipe with a metal loop for a stock, and it did not even have a pistol grip like many submachine guns did (and many still do). Also, the horizontal magazine was a notable part of the gun. Another feature of the gun was the fact that it fired the 9x19mm Parabellum cartridge, the standard German pistol and submachine gun round of the time. This was so that British soldiers could use German ammunition that they came across, making it cheaper to use. This gave assaulting troops and commandos a large supply of ammunition and a lighter footprint because they weren't dropping British or American magazines everywhere. However, this caused problems, as the magazine used the same arrangement style as the MP-40: two columns of 9mm cartridges in a staggered arrangement, merging at the top to form a single column. This made it easy for any dirt that got caught in the taper area to cause feed malfunctions. The gun was disliked by many people, who gave it the nicknames "Plumber's Nightmare", "Plumber's Abortion", or "Stench Gun". However, the advantage of the Sten was the ability to be easily mass-produced, even when there was a shortage during the war.
The Sten was put into service in 1941 and removed during the 1960s. In 1953 it was officially replaced with the Sterling submachine gun, but it wasn't until sometime in the 1960s that it was no longer in service.
The Sten Mk. II was the only common weapon used by British SAS in WWII because of its ability to be equipped with a suppressor.
The Sten, was air dropped by the British army for helping the Norwegian Rebel Groups, they were called Gutta På Skauen (Boys on the woods) and Milorg ( military organisation operating from the occupied Norway during WWII).
The first STEN, designed by Harold J. Turpin, had wooden furniture and a slanted flash hider. It also had a folding foregrip, a feature that was not seen on most of the subsequent STEN variants. The bolt was cylindrical with a fixed firing pin. These STENs were generally quite reliable and performed well, but they were quickly replaced by the cheaper STEN Mk.II.
The STEN Mk.I* was essentially the same as the Mk.I, but without the slanted flash hider and wooden furniture. It was made as a means of cutting down production costs. Together with the Mk.I, over 100,000 of these STENs had been manufactured by the end of the war.
The STEN Mk.II was the cheapest and the most common variant of the STEN gun. It was essentially the same as the Mk.I in terms of design, but it was simplified externally to reduce manufacturing costs, even more so than the Mk.I*. Mk.II STENs had detachable 2 groove barrels, rather than the 6 grooves seen on the Mk.I models, and there was no wooden furniture on the Mk.II. The result was an incredibly simple, light, inexpensive and very effective submachine gun. There were approximately two million Mk.IIs produced overall.
The STEN Mk.IIS was a suppressed version of the STEN Mk.II, designed for special operations. It saw service with British and French troops for special operations, and was probably the most widely-used suppressed weapon of the entire war. Another version, made by the SOE, was also designed, but was never serviced except with French special agents. It had a wooden stock.
The STEN Mk.III was first produced in 1943 by toy manufacturer Lines Bros. Even cheaper and simpler than the Mk.II, the Mk.III had a single-strut stock and a body made of cheap sheet metal that was welded at the top of the weapon. The barrel could not be detached. It was later manufactured by Long Branch Arsenal in Canada.
The STEN Mk.IV was aesthetically a lot different to the previous models in that it had a standard pistol grip and barrel shroud. It was also one of the few STEN variants to incorporate a flash hider. The unusual trigger guard of the Mk.IV was to facilitate for thick winter gloves. It also had a retractable stock. Internally it was identical to the STEN Mk.II. Although the Mk.IV was intended for paratroopers, it never saw service during the war. A suppressed version was also prototyped, but only one of these models was ever made.
The STEN Mk.IVB was similar to the Mk.IV, but it had a redesigned pistol grip and trigger guard. This was to improve the balance of the weapon. Otherwise, it was exactly the same as the Mk.IV. Both the Mk.IV and the Mk.IVB were rejected for service because they were allegedly uncomfortable to fire.
The STEN Mk.V was considered the best STEN variant. It was designed in 1944 and incorporated a wooden butt and pistol grip, and redesigned sights taken from a Lee-Enfield No.4 rifle. Internally it was much the same as the previous models. Reportedly very comfortable to fire compared to the Mk.II and Mk.III, the STEN Mk.V saw service with British paratroopers and special forces during the war. Some parachutists were issued models without the wooden butt, but a foregrip instead, to facilitate for firing whilst landing. A bayonet could also be fitted on the Mk.V.
The STEN Mk.VI was essentially the same as the Mk.V, but with a suppressor attached. The suppressor was the same as the one used on the earlier Mk.IIS. The STEN Mk.VI was issued to British Commandos, mostly for quietly eliminating enemy sentries.
Mark II (wooden butt model)Edit
This was a standard STEN Mk.II submachine gun with a wooden butt attached in place of the wireframe steel butt that most Mk.IIs were attached with. This wooden butt model was never serviced, likely due to the cost of producing it.
Mark II (Rosciszewski model)Edit
This was a STEN Mk.II modified by Antoni Rosciszewski of Small Arms Ltd. The magazine was mechanically operated by the breech block movement. The trigger was split into two sections, with the upper part of the trigger offering full-auto fire and a lower part offering single shots. It was very complex in design and never fielded.
Mark II (pistol grip model)Edit
This was a STEN Mk.II with a wireframe pistol grip, intended for use with paratroopers. It was compact but predictably uncomfortable to fire.
This was a STEN Mk.II modified with a 5-inch barrel and folding stock, as well as a conventional pistol grip and redesigned trigger guard. It was dubbed the "T42" in prototype phases, but was never serviced.
Mark III (wooden model)Edit
This was a STEN Mk.III with an wooden stock, and bayonet fittings. Sling swivels were also added. It was never serviced due to the costs associated with producing it.
Mark III (wooden model II)Edit
This was a STEN Mk.III entirely encased in an unusual bullpup stock, with the only external metal parts being the trigger, barrel, magazine and cocking handle. The trigger and pistol grip were in line with the magazine. The reasons for its creation are entirely unknown, but it was likely an experiment into increasing the comfort and handling of the weapon.
Foreign copies and derivativesEdit
International Ordnance MP2Edit
Cellini Dunn SM-9Edit
- Julio S. Guzmán, Las Armas Modernas de Infantería
- Weaponology: (Season 2 Episode 7) SAS
- Invasion Gun, Collier's Magazine: September 18 1943, P62