This is a 20 mm Oerlikon anti-aircraft machine-gun, which fires 450 rounds per minute with a muzzle-velocity of 820 m/sec. and a range of 2 km.

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Thisisa20mmOerlikonanti-aircraftmachine-gun,whichfires450roundsperminutewithamuzzle-velocityof820m/sec.andarangeof2km.