The GSh-301 (the actual Russian designation is GSh-301; also known by the GRAU index designation 9A-4071K) is a single-barreled, recoil operated autocannon weighing 46 kg (101 lb). Unlike many postwar cannons, The GSh-301 has a rate of fire of 1,800 rounds per minute, customarily limited to 1,500 rounds per minute to reduce barrel wear. The gun’s maximum effective range against aerial targets is 200 to 800 m and against surface or ground targets is 1,200 to 1,800 m.
When firing a continuous burst of 100–150 rounds, the barrel is put under so much stress that it has to be replaced. The gun uses an evaporation cooling system to prevent the detonation of a high explosive round inside a heated barrel. This cooling system consists of a cylindrical water tank around the rear end of the barrel. The GSh-301 is equipped with a unique pyrotechnic mechanism to clear misfires: a small pyrotechnic cartridge is located to the left of the 30mm cartridge chamber. This pyrotechnic cartridge fires a small steel bolt through the side wall of the 30mm cartridge. The hot propellant gases following the bolt into the dud 30mm round ignite the powder charge of that round and firing continues.
In combination with a laser rangefinding/targeting system, it is reported to be extremely accurate as well as powerful, capable of destroying a target with as few as three to five rounds. It has been deployed on several different types of fighter aircraft:
Its current manufacturer is the Russian company Izhmash JSC.
