how many times can you reload into a case? I'm sure there are a lot of variables involoved but on average, how long should the casings last and what are the tell tail signs that the case should be disposed of. I am mostly interested in 30-06 and 7mm remmag. thanks
Depends on the quality of the brass, chamber dimentions, power level of your loads, and how you resize the case.
I used to use W-W brass in my 30-06 for competition shoots. I could get 8-10 loadings with mid level loads. Similar results with a 243 Win.
My 338 RUM is about 6 loadings and my 280AL is so far 5 loadings and I haven't even needed to trim the cases.
Custom barrel, effecient case, and neck sizing cases are working well.
Some signs to look for that it is time to dump the cases:
1) The primer pocket is stretched out so that the primer seats too easily.
2) Look for a lighter colored ring in the brass just ahead of the base of the case.
3) The case has been trimmed more than 3 times (the trimmed off metal had to come from somewhere....that means the case is getting too thin.)
4) Look for hairline cracks in the neck.
5) Even if a light ring is not present, after 5 or so loadings, check the inside of each case by taking a bent paper clip and "feel" the sides of the inside of the case for depressions indicating the beginning of head separation.
6) This last one is controversial, but in my personal opinion, after the case has been loaded more than 10 times, no matter the condition, it gets dumped. I don't think the cost of new brass is worth the gamble.