The Birmingham Small Arms company of Birmingham, England, was founded in 1861 to manufacture rifle stocks. In 1863 the company built their factory at Small Heath and in 1866 they obtained a military contract to convert 100,000 muzzle-loading Enfield rifles into Snider breech-loaders. Two years later came orders for the complete manufacture of various military pistols and carbines. In 1873 a factory at Adderley Park was acquired for the manufacture of small arms ammunition, trading as the Birmingham Small Arms & Metal Company. This facility was disposed of in 1891 to the Nobel Dynamite Trust.
During the First World War, BSA factories produced 145,397 Lewis machine guns and 1,601,608 Lee-Enfield rifles. The company also began to take an interest in weapon development and in 1919 produced a -40 calibre military automatic pistol which failed to attract military attention. They then obtained a licence to develop the Thompson submachine gun patents in Europe and produced a number of prototype automatic rifles based on the Thompson designs, again without much commercial success. Another venture was the Adams-Willmott machine gun. Before the out- break of the Second World War the company had set up for production of the BESA tank machine gun and during the war developed the Besal or Faulkner machine gun. Anti-tank rifles, aircraft cannon and submachine guns, were also produced.
In postwar years the BSA submachine gun was developed, as was a 7mm automatic rifle, but neither gained military acceptance. Some of the 7.62mm FN rifles adopted after Britain standardised on the 7-62mm NATO cartridge were made by BSA.
After the First World War the company had entered the sporting gun field with an inexpensive shotgun, and they later followed it up with sporting and target rifles. Air rifles had formed part of the firm’s output since the early 1900s, and they were the developers of an unusual air rifle modelled on the service Lee-Enfield rifle and intended for inexpensive training of cadets and militia units.
BSA started to pro- duce submachine-guns in 1924 when they flirted briefly with the Thompson design from the US. This came to nothing, as did another licensing venture in 1939 for a Hungarian weapon designed by Kiraly. BSA put some effort into this latter model, including an element of redesign work, and it obviously disappointed them when the War Office showed no interest. Throughout the Second World War the company made weapons to government order, including Sten guns, but did no original work.
BSA submachine gun
The BSA submachine gun, submitted for trials in 1946-1949, was a compact and ingenious design in which the cocking action was done by rotating the forward handguard, thrusting it forward and back, and rotating it again to lock into place. This system meant that the firer retained his grip of the weapon throughout the cocking action, which was advantageous in the event of a feed stoppage. Of 9mm calibre, the gun had a magazine which, with its housing, could be folded forward alongside the barrel giving compact dimensions for packing and, again, allowing rapid action in the event of a malfunction. But in competitive trials, it suffered from having had less development time than its competitors and was rejected for military service. The same fate befell the P-28 automatic rifle, a weapon of great promise. It was an exceptionally clean design, using a laterally-locking bolt, but the abandonment of the projected British .280 cartridge in favour of the 7.62mm NATO round put an end to its chances.
British submachine-gun. The Welgun was one of many British attempts during the Second World War to produce a very small and light submachine-gun. It was called for by the Special Operations Executive (SOE) which were at that time in Welwyn, hence the first part of the name. It was designed and built by BSA in Birmingham and the first military trials were in early 1943. From then on there seem to have been several trials, in all of which the Welgun fared quite well, but it was never adopted, not even for the SOE.
The design used some Sten components. The barrel, magazine and return spring were Sten, but the design was most compact. The spring was around the barrel and two long plates ran forward from the bolt to a ring in front of the spring. There was a stop just in front of the breech and rear movement of the bolt compressed the spring against this stop. The plates had serrations on them, and these were gripped to cock the weapon. The Sten magazine fed vertically upwards and the barrel was enclosed in a tubular jacket. The trigger mechanism was very simple, almost crude, and the safety was an external rocking bar which held the bolt either open or closed. A simple folding steel stock was fitted.
The bolt had a floating firing pin actuated by a plunger and rocking bar. When the bolt closed on the breech the plunger was pushed in and operated the rocking bar. This pushed the firing pin forward to fire the cartridge. With a little development the Welgun could probably have been every bit as good as the Sten, and perhaps better, but by then the Sten was already in production.