The pistol that would eventually be named the Colt Commander was Colt's Manufacturing Company's candidate in a U.S. government post-World War II trial to find a lighter replacement for the M1911 pistol that would be issued to officers. Requirements were issued in 1949 that the pistol had to be chambered for 9 mm Parabellum and could not exceed 7 inches in length or weigh more than 25 ounces.
Candidates included Browning Hi-Power variants by Canada's Inglis and Belgium's Fabrique Nationale, and Smith & Wesson's S&W Model 39. Colt entered a modified version of their M1911 pistol that was chambered for 9 mm Parabellum, had an aluminum alloy frame, a short 4.25-inch barrel, and a 9-round magazine. In 1951, Colt moved their candidate into regular production. It was the first aluminum-framed large frame pistol in major production and the first Colt pistol to be originally chambered in 9 mm Parabellum. The first year's production included 45 ACP and 38 Super chamberings.
In 1970, Colt introduced the all-steel "Colt Combat Commander", with an optional model in satin nickel. To differentiate between the two models, the aluminum-framed model was re-named the "Lightweight Commander"
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