The Mauser BK-27
|Place of origin||Germany|
|Used by||See users|
|Designer||Mauser (now Rheinmetall)|
|Manufacturer||Mauser (now Rheinmetall)|
|Weight||100 kg (220 lb 7 oz)|
|Length||2.31 m (7 ft 7 in)|
|Barrel length||1.73 m (5 ft 8 in)|
|Caliber||27 mm (1.063 in) caliber|
|Rate of fire||1,000-1,700 rpm (+/- 100rpm), selectable|
|Muzzle velocity||1,100 m/s (3,600 ft/s)|
The BK 27 (also BK27 or BK-27) (German acronym for Bordkanone, "on-board cannon") is a 27 mm (1.063 in) caliber revolver cannon manufactured by Mauser (now part of Rheinmetall) of Germany. It was developed in the late 1960s for the MRCA (Multi Role Combat Aircraft) program that ultimately became the Panavia Tornado.
The BK 27 is a gas-operated cannon firing a new series of 27x145 mm projectiles with a typical weight of 260 g (9.2 oz). Most models use a linked feed system for the ammunition; however, the Eurofighter Typhoon makes use of a specially developed variant of the BK 27 that uses a linkless feed system instead, which is intended to improve reliability.
The Mauser BK 27 is used in the Panavia Tornado, the Alpha Jet, the JAS 39 Gripen, and the Eurofighter Typhoon. At one time the USAF was considering to license its production for the F-35 Lightning II joint strike fighter, but those plans have been cancelled in favour of the GAU-22/A.
Rheinmetall has also developed remote controlled naval versions, the MN 27 GS and the MLG 27 fully automatic naval guns, which are installed on many ships of the German Navy. Ninety-nine MLG 27s have been ordered by the German Navy so far. The cannon is a single-barrel, high performance, breech-cylinder gun operated by a fully automatic electrically fired gas-operated system at a selective rate of 1000 or 1700 rounds per minute. The Mauser BK 27 utilizes pyrotechnic cocking charges to cycle the action.
The BK27 has a much lower nominal fire rate than the M61 Vulcan, but its fire rate is constant throughout shooting due to the fact the cannon need not spin up. As a result, in conjunction with the higher caliber, the Mauser BK 27 fires in the first second 4 kg of projectiles in contrast to the 2 kg of the M61 Vulcan which also needs about 25kW electrical energy on the maximum fire rate.
- Type: single-barrel revolver cannon
- Caliber: 27 mm x 145 (1.063 in)
- Operation: revolver
- Length: 2.31 m (7 ft 7 in)
- Weight (complete): 100 kg (220 lb)
- Rate of fire: 1,700 rpm (+/- 100rpm)
- Muzzle velocity: 1,100 m/s (3,600 ft/s)
- Muzzle energy: ~157,300 Joules
- Projectile weight: 260 g (9.2 oz)
- ADEN cannon - comparable British design
- DEFA cannon - comparable French design
- M39 cannon - comparable US design
- Ian, V. Hogg; Terry, J. Gander (1998). "Cannon - 20 to 30 mm cannon: 27 x 145 B ammunition (Switzerland)". Jane's Ammunition Handbook. Jane's Information Group. ISBN 9780710617897.