After the commercial failure of Gordon Ingram’s M6 submachine gun in the early 50s, we would radically change the layout of his designs. Instead of a Thompson lookalike Ingram’s M10 (the M7, M8, and M9 doing experimental prototypes only) would be a boxy and compact affair with a Czech-style telescoping bolt. It found little interest until a meeting between Gordon Ingram and Mitch WerBell resulted in WerBell demonstrating it to excited military audiences in Vietnam in 1969.

WebBell was an ex-OSS man who had started a company called Sionics, selling suppressors to the US military. He thought the combination of Ingrams submachine gun and his suppressor would be a fantastic package, and he found plenty of interest in special operations personnel in Vietnam. He would create the Military Armament Corporation based at his farm in Powder Springs, GA and entice Ingram to join as his chief engineer. The result would be the .45ACP M10, a 9mm version of the M10 (made for use with subsonic 9mm ammunition), and a scaled-down .380 ACP M11 submachine gun.

MAC would have a short life, with all its assets sold at a bankruptcy auction in April 1976 - but it had plenty of time to create what would become an iconic gun - the Big MAC. Many imitations and copies would follow, but Powder Springs was the home of true original Ingram M10 and M11 submachine guns!