I just had a thought...what if the case lengths are slightly different, say .015 to .025. Wouldn't that come into play? I just cripmed a bunch the other night and some crimmped differently. I know that some of the cases were slightly different in length because I had just mic'd them all and trimmed the one's that were out of tolerance. I'm working .308 win, and try to come in around 2.01 to 2.02 case length. I consider these to be within torlerable limits for my guns. Might slightly different case length be part of the problem?