On the cases that cause a sticky bolt, mark them with a permanent marker so you can tell them apart. Now chamber the marked cases and see if the bolt closes hard compared to a case you did not mark. Measure the head space and compare it to the case that don't cause a sticky bolt. You will most likely find the head space is to far out. Now full length resize and trim to length. It will most likely chamber just fine. There is a point in time when you can't neck size anymore.