That repair is for guns that the owner isn't going to pay for a new bolt like it or not you can blow a gasket talk crap but that's the way it is .senario ,guy walks into a gun shop says my guns lose gunsmith looks and say 20 pounds for a new bolt!,, guy..I only paid 10 pounds for the entire gun ?well for 50 p I can work up the lump ..guy says work up the lump it is..see how that works brentd