BSA experimental model 1949

Lore & Background

Following the end of World War Two, the British Army sought a replacement for the Sten submachine gun, which had been in service since 1940. The Sten was simple, cheap and unrefined, and while this crudity was an asset during wartime, a more refined and durable variant was requested. The Sten Mark V was developed in 1944, adding a wooden stock, forward pistol grip and better construction. By the late 1940s, the British Army was testing replacements, including the Welgun developed by BSA and a design from Enfield. However, the Patchett Machine Carbine Mk 1, made by the Sterling Armaments Company, was chosen and entered service as the Sterling submachine gun in 1953.

Another contender was the BSA 'Experimental Machine Carbine, 1949' (EMC). Chambered in 9 mm Parabellum, it used a side-mounted 32-round box magazine shared with the Sten and later the Sterling. The EMC used blowback action and cycled at 600 rounds per minute, faster than the Sterling and earlier Sten variants. It featured a Bakelite pump-action foregrip, a hinged magazine insert that could be pivoted backwards to clear jams without removing the magazine, and a safety switch in the pistol grip operated by the user's thumb. Despite these innovative features, the design was not adopted.

The BSA Machine Carbine is a blowback-operated, magazine-fed weapon. Unusually, it lacks a bolt handle; instead it has a pump-action foregrip operated by pushing it forward and then pulling it back, which pushes a bar that cocks the bolt. The grip is then rotated slightly to disengage the bar and allow the bolt to cycle once fired. In response to the Welgun's open receiver, the EMC was enclosed with only the magazine insert and ejection port open when firing. When the bolt was closed, these openings were covered, minimising the chances of dirt entering the action.

Reader's Guide

The BSA Experimental Model 1949 represents a notable but unsuccessful attempt to replace the Sten submachine gun in British service. Its development occurred during a period of post-war reassessment, when the British Army tested several designs including the Welgun and a model from Enfield. The EMC introduced several unusual features, such as a pump-action foregrip that replaced the conventional bolt handle, a hinged magazine insert for easier jam clearing, and a thumb-operated safety switch. The enclosed receiver, which covered openings when the bolt was closed, addressed the dirt ingress issues of the open-receiver Welgun. Despite these innovations, the design was not adopted; the Patchett Machine Carbine Mk 1 from Sterling Armaments Company was chosen instead and entered service as the Sterling in 1953. The EMC's faster rate of fire and unique operating mechanism did not overcome the preference for the Sterling's more conventional design. Its legacy is that of a technically interesting but ultimately unsuccessful competitor in the post-war British submachine gun trials.

Did You Know?

• The EMC used a pump-action foregrip instead of a conventional bolt handle to cock the weapon.
• When the bolt was closed, the ejection port and magazine insert were covered to keep out dirt.