Are all of these cases fired in your rifles? Are they fired in different rifles you own? Are some fired in your rifles and some from other guns?
The cases fired in your guns should be measured, then the sizer set up to push the shoulder back 0.002 to 0.008 inches. The fixed drop in case gages I've used all set the sizer up for 0.008 inches of head space. I use 0.002 inches in my autoloaders and have never had a function problem. But insure you have some headspace, a case that is just a thousandth too long will cause a failure to eject with a loaded round, and probably won't chamber easily (but that is harder to catch as the bolt carrier can jam it into battery anyway).
If you have rifles that form cases to radically different dimensions, the brass will need to be segregated. For example, I have a Garand chambered for .308 Win in which new Winchester cases come out 0.011 inches longer after firing. The cases barely move in my single shot 40X and stretch only a couple of thousandths in my M1A. So, I'm stuck with separate ammunition for the Garand (plus a trip to a gunsmith with a set of chamber gages when I get a chance).
Cases from unknown sources should be full length sized to the degree your die can, not only to reshape the diameters, but also to straighten the cases. As long as they are no shorter than about 0.014, I wouldn't worry about it much - measure new, loaded factory ammunition to set yourself a bench mark.