Colt's Manufacturing Colt Viper, Revolver, 357 Magnum, 3 Barrel, Stainless Steel Finish, Traditional Walnut Grips, Black Ramp Front & U-Notch Rear Sight, 6 Rounds VIPER-SP3WRR The Colt Viper features a 1/2 lug barrel design to reduce weight and increase concealability. The forged stainless-steel construction delivers a robust shooting experience and is paired with a one-piece barrel with a recessed target crown. Chambered for 357 Magnum and accepts 38 Special Cartridges.