I'not seen any cracking of the bolts on mausers but I have seen numerous cases of setback of the lugs in the receiver. Most often, this occurred in actions which were loaded real hot and/ or had been opened up for a magnum cartridge. The upper locking lug seat ended up with a ridge corresponding to the ejector slot in the left lug. I suppose this could be corrected by machining and re-heat-treating but I would not bother. GD
