Originally Posted by 358Hammer
Once I have a case fire formed to a chamber I never size the body again. In fact my neck sizer is well off the shoulder junction.
Unless you have a chamber that is too long, either use a neck sizing die or move your die out away from the shoulder half a turn and I think you will be fine. Cases fired in a precision chamber will pretty much always remain the same size.
Well used hardened cases will tend to get brittle. Actually that isn't totally true as I have seen cases do what you are indicating right out of the new container. Some shoulders will size down and some will spring back from memory or other reasons.
No clue about your measuring techniques. A 2 thou difference can very easily be made in technique or equipment.
Neal