Abstract: A revolver has a cylinder mounted so that actuation of the hammer will cause the hammer to strike one end of a cartridge in a chamber of the cylinder. The cylinder is mounted for rotation about a center pin, and a bolt having a projection at one end is aligned with the center pin to release it for lateral swinging movement of the cylinder away from the recess. A first spring member is associated with the center pin for urging it rearwardly, and the bolt has an abutment slidable into and out of the path of pivotal movement of the hammer. The revolver is modified by a second spring member associated with the abutment which overcomes the first spring member to urge the abutment into a position in the path of the hammer. A manually engageable slide is engageable with the bolt and movable in a first direction causing the projection to engage the center pin to release it from the frame and further movable in a second direction causing the abutment to slide out of the path of pivotal movement of the hammer.