Machine Carbine, Experimental Model No.2 (MCEM 2)
Like BSA’s EMC 1949 the MCEM 2 manufactured by Enfield was one of several attempts to design a new submachine gun to replace the STEN for the British military. Like the EMC the Machine Carbine, Experimental Model 2 (MCEM 2) had some revolutionary design features.
The MCEM 2 was designed by a Polish emigre, Lieutenant Jerzy Podsędkowski working at the Royal Small Arms Factory at Enfield during the late 1940s. It featured one of the first uses of a telescopic bolt, this dramatically shortened the length of the weapon by having part of the bolt surround the breech and part of the gun’s barrel rather than have the bolt behind the breech.
The MCEM 2 was one of a series of experimental submachine guns developed by Enfield. This series included the MCEM 1 designed by Harold Turpin, co-designer of the STEN gun, and a slightly more conventional design the MCEM 3. There may have been up to as many as six MCEM designs.
The MCEM 2 fed from an 18-round box magazine which was loaded through the weapon’s pistol grip. This feature coupled with the MCEM 2’s telescopic bolt are both also seen in the Uzi which was designed several years later.
The MCEM 2’s small size made it more of a machine pistol than a submachine gun, with its shoulder stock able to double as a canvas holster. The grip magazine housing gave the short submachine gun stability making it easy to handle one handed. The MCEM 2 would have made an excellent side arm for mobile troops, tank & crews - perhaps issued instead of a pistol or carbine.
Chambered in 9mm and weighing just 2.5kg the MCEM 2 used a blowback action with the striker positioned at the rear of the receiver with a small portion of the bolt to the rear of the breech and the rest surrounding the barrel. The initial prototypes cycled at approximately 1000 rounds-per-minute which would have emptied the 18-round magazine in under three seconds. Attempts were made to lower the cycle rate with one prototype averaging a more manageable 700 rounds-per-minute. However, due to this high rate of fire and the unusual design a more conventional design was eventually chosen, the Sterling Submachine Gun. The MCEM 2’s revolutionary design would later be copied or at least influence later successful telescopic bolt designs like the Uzi.
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