Type 97 20 mm anti-tank rifle

Type 97 Automatic Cannon
Type 97 Automatic Cannon
Type	Anti-tank rifle
Place of origin	Empire of Japan
Service history
Used by	Imperial Japanese Army
Wars	Second Sino-Japanese War, Battle of Lake Khasan Battles of Khalkhin Gol World War II
Production history
Designed	1937
No. built	1200
Specifications
Weight	50 kg (unloaded)
Length	2100 mm
Barrel length	1250 mm
Caliber	20 x 125 mm
Action	Gas-operated
Rate of fire	12 round/min
Muzzle velocity	750 m/s (2,460 ft/s)
Feed system	7 round detachable box magazine

The Type 97 20-mm antitank rifle is a Japanese semi-automatic anti-tank rifle used before and during the Second World War. Adequate for the early part of its deployment, it was rendered obsolete by advancement in tank armor.

The Imperial Japanese Army (IJA) had found itself in need of an effective anti-tank defence for its infantrymen during the numerous border clashes with the Red Army along the Manchurian border in the mid 1930s. Originally designed to take on the Soviet BT and T-26 tanks, the Model (Type) 97 was accepted into service in 1937 and production began in 1938 by the Kokura Arsenal. Production ceased in 1941 after 1,100 rifles had been made due to advancement in tank armor making the 20 mm round obsolete. Due to emergency war demands, production was ordered again, and 100 rifles were built by the Japanese Steel Works in 1943 for a total production figure of approximately 1,200 rifles.

Sometimes referred to as an anti-tank machine (or automatic) cannon, it could be carried by two men in any terrain. The weapon had a semi-automatic action which gave it a high rate of fire. On the downside the recoil from the large round was very violent. The gun could be fitted with a protective shield pushing the total weight up to 68 kg (150 lb). The Ho-1 and Ho-3 automatic aircraft cannon were developed from the Type 97.

Armour penetration was 30 mm at 90° at 250 metres.

The Type 97 antitank rifle first saw combat against the Red Army's BT5/7 tanks at the Battles of Khalkhin Gol in 1939. The rifle stayed in service as a front line weapon throughout World War II in all theaters of operation primarily serving as a heavy weapons infantry support system, since the 20 mm round was no longer effective against tank armor after 1942.

Some were adapted for use in 20 mm armed defensive turrets on the Ki-49 bomber as the Ho-1, and some put into the Ki-45 Ko and Ki-45 Hei as front facing 20 mm armament as the Ho-3.