It is NOT the half cock being engaged as a safety on Colt model P type sixguns. I have never seen anyone using the HALF cock in that manner. Doing that would be more dangerous than using the safety The Colt model P, old model 3 screw Ruger's, and faithful copies have an unsafe safety notch in the hammer for the sear to drop in. The very first click you hear in these guns when cocking the hammer is the sear riding over that notch. The engagement of the sear in this notch prevents the firing pin from touching the cartridge primer, however, this safety is extremely unsafe in actual use and general carry. The sears on these type guns is thin and brittle and any direct hard contact will cause the thin sear tip to break off allowing the hammer to strike the primer and fire the gun. My personal experience was from the gun falling from chest high to a hard floor, concrete covered with thin carpet, and the butt of the gun striking the floor hard enough that the sear 'bounced' out of the notch and the hammer fell hard enough to fire the gun. Nothing broke, not a mark on the gun, 3 people in the room very near the incident, no one injured. .22 WMR Colt Frontier Scout. I never found the bullet nor a bullet hole anywhere in the room.