Auto Ordnance 1927A1 Deluxe, Semi-automatic, 45ACP, 10.5 Barrel, Black Finish, Walnut Stock, Adjustable Sights, 20Rd Stick Magazine, (Will Accept 30Rd Drum Magazine) Carry Case T1SB The Thompson short barreled rifle (SBR) is our gun that is closest in dimensions and weight to the original submachine gun made famous during the 1920's in the hands of gangsters and G-men. Its operation is semi-auto, firing from a closed bolt, and featuring a 10.5" barrel. The frame and receiver are machined from solid steel and the stock is genuine American walnut. The finish is blued steel.