A pyrotechnic cocking charge is a device used to cock or re-cock a
gas-operated
Gas-operation is a system of operation used to provide energy to operate locked breech, autoloading firearms. In gas-operation, a portion of high-pressure gas from the cartridge being fired is used to power a mechanism to dispose of the spent ...
automatic cannon
An autocannon, automatic cannon or machine cannon is a fully automatic gun that is capable of rapid-firing large- caliber ( or more) armour-piercing, explosive or incendiary shells, as opposed to the smaller-caliber kinetic projectiles ( bu ...
, such as the
Mauser BK-27
The BK 27 (also BK27 or BK-27) (German abbreviation for ''Bordkanone'', "on-board cannon") is a caliber revolver cannon manufactured by Mauser (now part of Rheinmetall) of Germany. It was developed in the late 1960s for the MRCA (Multi Role Com ...
or the
Gryazev-Shipunov GSh-6-23. Such devices are not necessary in an externally powered cannon, such as the electrically driven
M61 Vulcan, where the external power source is used to operate the mechanism of the weapon. The number of charges carried varies by design – the
GSh-6-23
The Gryazev-Shipunov GSh-6-23 (russian: Грязев-Шипунов ГШ-6-23) (GRAU designation: 9A-620 for GSh-6-23, 9A-768 for GSh-6-23M modernized variant) is a six-barreled 23 mm rotary cannon used by some modern Soviet/Russian military ...
has a generous complement of ten, while others have as few as one. One of the benefits of an automatic cannon that isn't powered electrically is that 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.
Autocannon
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