Ruger GP100 Standard, Double/Single Action, Revolver, 357 Magnum, 6 Barrel, Alloy Steel, Blued Finish, Hogue Monogrip, Ramp Front and Adjustable Rear Sights, 6 Rounds, GP-161 01704 The Ruger GP100 Double-Action Revolvers are among the most comfortable shooting revolvers. The triple-locking cylinder is locked into the frame at the front, rear and bottom for more positive alignment and dependable operation shot after shot. It's patented grip frame design easily accommodates a wide variety of custom grips and the patented transfer bar mechanism provides an unparalleled measure of security against accidental discharge. With no special tools required, maintenance and assembly is easy.