The Winchester Model 12 was the first truly successful hammerless pump-action shotgun and the dominant American pump shotgun from its introduction until the Remington 870 eclipsed it in sales in the 1950s. Over 2 million produced between 1912 and 1963. Called "The Perfect Repeater" — the machined steel receiver and tight manufacturing tolerances gave it a smoothness of operation unmatched by any pump shotgun before or since. Used in both World Wars as the "Trench Gun" with bayonet lug and heat shield. Available in 12, 16, 20, and 28 gauge. Winchester briefly reintroduced it (1972-1980) before definitively discontinuing. Type: Shotgun Action: Pump-Action Caliber: 20 gauge Capacity: 6 Year introduced: 1912, USA Weight: 150.4 oz Overall length: 48" Status: Discontinued Intended use: hunting, collector, historical, competition