The Gast Gun is a German twin barreled machine gun developed by Karl Gast of the 'Vorwerk' company and used during the First World War. It was notable for its high rate of fire of 1,600 rounds per minute and unique mechanism, short recoil mechanism of one barrel operated the breech of the other barrel. The .Gryazev-Shipunov GSh-23L series of Russian aircraft cannon use a gas-operated version of this system. Picture below is the 13.2mm Gast-Flieger MG.
