The GP100 is Ruger's mid-frame service revolver with a 4.2-inch barrel, fully adjustable rear sight, and triple locking cylinder. Known for an indestructible reputation; it outlasts any .357 Magnum load. Type: Revolver Action: Double-Action Caliber: .357 Magnum Capacity: 6 Year introduced: 1986, USA Weight: 40 oz Overall length: 9.49" Status: Active Intended use: Service, Defense, Hunting, Competition