I was fire forming 50 new Hornady 375 HH cases various loads includeing cast bullets.After fireing the 50 rounds off I FL. resized them in a Lee die. I could see a problem right off, there was a ring of brass scraped off almost like a very thin second belt.If you pushed hard enough with your thumb nail you could break it off.So I took a new Win. case and did the same proceedure no problems at all everything looks normal.What do you think is happening are these cases safe to use?