I had a small hole about 1/4" above the head of the case form when fire forming new factory lapua loads. After about a dozen loads like this it burned a hole in my chamber. I had the barrell shortened and rechambered. Now the same problem is happening. The cases have the same exact shape hole and in the exact same spot both before the rechamber and after. Note: not every single case formed does it, ~ 80% do. I am wondering if I should empty and reload the factories with cream of wheat loads? Could I just have a bad batch of lapua's? Also not the case has a small bulge on the opposite side of the case and the hole is about the size of the shaft of a pin. I don't want to ruin the barrel again. I have not had a reloaded shell do this yet. Any help is very much appreciated!