You asked a good question. If you shoot a lot, here's what I suggest: Neck size with a neck sizing die or neck size by using a FL sizing die to Partial Resize the cases (Google that up). After several reloadings in this fashion, where you have not reset the case shoulder, and depending on how hot your loads are, fired cases will become a bit harder to chamber in your rifle. At this point, switch to the FL sizing die. You want to resize the fired cases JUST ENOUGH that they will chamber easily, so back the die out and size a case. It'll still be hard to chamber. Screw the die in 1/4 turn and try again. Do this till the resized case chambers easily. Lock the die ring right there.
There are other ways to do the above, using more equipment, but I have outlined an easy cheap way to do what you need.
One thing to mention is that using the neck die as suggested is better than doing a partial resize, depending on the case design. Cases with body taper (270) partial resize well. Cases with little or no body taper (260, 308) probably won't partial resize well.