In the aftermath of World War One, the Japanese military saw the utility of infantry-portable light grenade launchers instead of rifle grenades, and adopted the Type 10 in 1921 (Taisho 10). It went into production in 1923 at the Tokyo Army Arsenal, although the great Tokyo earthquake led to production being moved to Nagoya, where about 11,000 were made between 1925 and 1937. The Type 10 was a remarkably light and handy weapon, weighing just 5.5lb (2.5kg) and disassembling into a transport configuration the size of a wine bottle.
The larger Type 89 grenade launcher was adopted in 1929, which led to the older Type 10s being relegated to use for illumination and signaling, which they did through the end of World War Two.
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