The body section of the die can squeeze the case in such a way that the shoulder, and hence the shoulder/neck junction, moves forward. So when the length of the neck is sized and the mark stops at the junction the shoulder is forward of its best position.
Thank you for your reply. I have done what I posted for a few rifles but I checked the brass for ease of chambering. Doing what I posted and checking the brass in the chamber and turning the die down if necessary would work wouldn't it?
