Many years ago I seen the same thing happen with an U/O shotgun, you could clearly read Win AA 12 GA on the breech face, probably could have read it if you were blind also as the letters were very raised, as you would expect the shotgun was destroyed, SKB if my memory serves me right, the owner was lucky, two very black eyes to show for his first effort at reloading, for this reason I always implore people who are new to reloading to read everything from the instruction manuals for setting up reloading presses and reputable reloading manuals, there is a lot of pressure being released only inches from your head