It will be swaged down to bore size as soon as it enters the bore. from there on it will be ok. the problem happens when the load is hi and it will peak too high to fast it is just too risky to use over sized, when you swag them down you will be ok. I did some experiments with over size bullets with factory powder loads and the first sign was the bolt got hard to open. at .004 oversize and I had to use a wooden mallet to open the bolt. I made a rifle holder and fired from a safe place. I did destroy the rifle in case there was any stress damage to the metal I diden't want someone to get hurt.
