Gryazev-Shipunov GSh-6-23

The Gryazev-Shipunov GSh-6-23 (Грязев-Шипунов ГШ-6-23) (GRAU designation: 9A-620 for GSh-6-23, 9A-768 for GSh-6-23M modernized variant) is a powerful, fast-firing six-barreled 23 mm Gatling gun used by some modern Soviet/Russian military aircraft.

The GSh-6-23 differs from most American multi-barreled aircraft cannon in that it is gas-operated, rather than externally powered via an electric, hydraulic, or pneumatic system. Although the engineering difficulties involved in producing a gas-operated rotary cannon with such a high rate of fire are considerable, they create less of a drain on the aircraft's power systems, and they accelerate to their maximum rate of fire much more quickly. There is less "spin-up" time for the barrels than with an externally powered rotary cannon, a significant advantage in aerial combat, where the window of opportunity to place multiple rounds on target can be vanishingly short.

The GSh-6-23 uses the 23x115 Russian AM-23 round, fed via linked cartridge belt or a linkless feed system. The linkless system, adopted after problems with the belt feed, is limited to 8,500 rpm. Fire control is electrical, using a 27v DC system. The cannon has 10 pyrotechnic cocking charges, similar to those used in European gas-operated revolver cannons such as the DEFA 554 or Mauser BK-27.

The GSh-6-23 has an extremely high rate of fire, with maximum cyclic rates of 9,000 to 10,000 rounds per minute. Compared to the U.S. M61 Vulcan, the GSh-6-23 fires 50-66% more rounds per minute, has a heavier projectile, but lower muzzle velocity. The weapon is also lighter and shorter. The rapid rate of fire exhausts ammunition quickly: the MiG-31 (800 rounds maximum) aircraft, for example, with 260 rounds of ammunition, would empty its magazine in less than two seconds.

The GSh-6-23 is used by the Sukhoi Su-24 'Fencer' attack aircraft, the MiG-31 'Foxhound' interceptor aircraft, and the now-obsolete Sukhoi Su-15 'Flagon' among others. However, after two Su-24 were lost because of premature shell detonation in 1983, plus some different problems with gun usage (system failures, etc.), usage of the GSh-6-23 was stopped by a decision of the Soviet A.F. Command. For now all aircraft in the Russian A.F. are flying with fully operational guns, but without ammunition.

It is also used in the SPPU-6 gun pod, which can traverse to -45° elevation, and +-45° azimuth.