27-mm BK 27 Mauser cannon

The German Mauser 27-mm BK 27 automatic weapon is an electronically fired, gas-operated, single-barrel, five-cylinder revolver cannon. It was developed from World War II-era German weapons and resembles the French DEFA 550 series in concept.

Compared to the contemporary DEFA 553, the BK 27 has a higher rate of fire and muzzle velocity. The choice of 27-mm caliber produced the best combination of projectile mass and rate of fire in an internally mounted airborne gun. Its ammunition...