Hi All, I have a new Mossberg 590 Shockwave. I was at the range today shooting it and when I got home and started cleaning it, There were lots and lots of metal shavings coming out of the barrel. The gun was clean before I started shooting it. I was afraid the lining of the barrel was coming off, but eventually I was able to clean them all out. I was shooting 00 Buck (9 lead pellets). Is this normal when shooting lead buckshot? I have limited experience with shotguns and would appreciate any help.