Originally Posted by
mauser06
hmmm maybe im doing things wrong....but my 35 whelen brass i fired that was trimmed to length after i took it outta the bag, is longer after being fired than it was when i got it new...i trimmed a few 1x fired cases to use as fliers before i started shooting my groups and i trimmed more off the cases than i did when they were new...didnt measure them and the trimmer is still setup...
im about as new as they come to reloading and figured that you always trim your cases to that size....if nothin else, mine will be consistant i guess..but maybe im doin things wrong?
I am trim happy myself. (that sounds kinda funny) Anyway, I think new brass will stretch a little more than normal the first time you fire it. I the case gets blown out fully and then when you resize it it gets longer. Subsequent firings shouldn't be so bad unless you are really pushing the shoulder back.
I don't think trimming is a big deal myself. I do it because I'm anal. If you are crimping, you need consistent length, and trimming becomes more important. When cases get too long, they jam into the end of the chamber, and pressures can get dangerous. Those are the main reasons to trim.
I guess what I should do is check cases when new and trim if needed, trim after the first firing, and then monitor them after that.