It is surprising to some gun owners who bring semi-auto firearms to me with the complaint that "will not eject empty cases or reload" and find that it is nothing more serious than WD-40 which they have sprayed into the action. It then gums up and causes the gas piston to seize. The Break Free lube is MUCH superior to WD-40 as a lube for PTO shafts etc. 73, Frank, K4VMO