I was cleaning brass in my ultrasonic cleaner the other day. I usually dry by throwing the brass in a pan and baking at 200 degrees for 20 minutes or so. This day the wife was baking and so I held off. I was watching a game and she offered to put the brass in with her baking and I didn't think. It was about 400 degrees. When I pulled the brass out it looked case-hardened, with blue hues over much of it. Did I case harden the brass without realizing it? It was all my 7.62x54R brass and a hundred pieces or so of my .38 special brass. Do I have to throw them away or can I use them safely? Anybody know?