During World War Two, Canada supplied some 73,000 Sten guns (made by the Long Branch arsenal) to Chinese Nationalist forces in an effort to help them fight the Japanese. These Stens were standard MkII pattern guns, chambered for the 9x19mm Parabellum cartridge. However, many of these were eventually converted to 7.62mm Tokarev ammunition, especially after the victory of the Communist forces over the Nationalists. The conversion involved a new barrel and new magazine and magazine well. The 7.62mm barrels were typically longer than the original ones, and the magazine of choice was that of the PPS-43. Some were done by installed a magazine adapter into the original magazine well, and some (like this one) were done by cutting off the original magazine well and replacing it with a new one. In addition, some Sten guns were made domestically in China, both in 9mm and 7.62mm. The 7.62mm Tokarev cartridge was popular both from Russian pistols and submachine guns and also from China's long military use of the dimensionally-identical 7.63mm Mauser cartridge in C96 pistols.

Many thanks to the Royal Armouries for allowing me to film and disassemble this interesting submachine gun! The NFC collection there - perhaps the best military small arms collection in Western Europe - is available by appointment to researchers.