Chain gun
Firearm mechanism that uses an external source of power to cycle the firearm / From Wikipedia, the free encyclopedia
A chain gun is a type of autocannon or machine gun that uses an external source of power to cycle the weapon's action via a continuous loop of chain, similar to that used on a motorcycle or bicycle, instead of diverting excess energy from the cartridges' propellant as in a typical automatic firearm.[1][2]
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