Type 1 47mm Anti-tank Gun. The Type 1 47 mm anti-tank gun was an anti-tank gun developed by the Imperial Japanese Army and used in combat during World War II. The Type 1 number was designated for the year the gun was accepted, 2601 in the Japanese imperial year calendar, or 1941 in the Gregorian calendar. The Type 1 47 mm anti-tank gun was accepted into service in 1942. The design originated as an improvement to the prototype “Experimental Type 97 (1937) 47 mm anti-tank gun,” which was tested between 1938 and 1939. The prototype weighed 567 kilograms with a barrel length of 2,515 mm, a traverse range of ±50 degrees and an elevation range of between minus 10 and plus 20 degrees, and a muzzle velocity of 730 m/s. The prototype was not accepted into service because it was considered to not have sufficient performance. After the Nomonhan Incident, the Imperial Japanese Army started the development of a new anti-tank gun, considering that the Type 94 37 mm anti-tank gun would likely b...