Winchester Model 12 pump action shotgun in 12 gauge, a popular weapon as a trench gun and in its riot gun configuration as shown here. tube magazine holds five shells usually in 00 Buckshot. Frequently used to escort & guard POW's.
Model 12 trench gun?, Winchester Military Arms
Classic Guns: Winchester Model 1897 'Trench Gun
Firearms History and the Technology of Gun Violence – UC Davis Library
Winchester Model 12
Winchester Model 1895 at Fallout New Vegas - mods and community
Winchester Trench Shotgun with Winchester 1917 Bayonet
Thompson submachine gun, Military Wiki
Winchester Model 12 - Arms and other weapons - The Great War (1914
Winchester model 12 from 1921
Winchester model 12 help
Classic Guns: Winchester Model 1897 'Trench Gun