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In the 1960s, the military began exploring modern variants of the electric-power, rotating barrel Gatling gun-style for use in the Vietnam War. In order to develop a weapon with a more reliable, higher rate of fire. General electric designs scaled down the rotating barrel 2omm MGI vulcan cannon for ammunition.

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Several larger aircraft were outfitted with mini-guns, specifically for close air support, including famous gunship airplanes. The resulting weapon designated XM134 and known popularly as the Mini-gun. It could fire up to four thousand rounds per minute without overheating.

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