Case life is going to be affected by both the gun you're using and your reloading technique. If you over-work the brass you will shorten case life. If you load very hot loads the primer pockets will give out sooner.

In a bolt action if you neck size only most of the time and don't push the limits you can expect pretty good life out of the cases. I'm on the 8th reloading of a set of 300WM brass and haven't had to toss one of the lot yet.

Watch for loose primer pockets or a light colored ring in front of the case head (impending separation). Toss if you find either one.