I would think that if the chamber is 0.5140" just in front of the belt then the cases would measure 0.5140" after firing. Upon firing the case expands to fill the chamber, right? Even with lighter loads, right? So why do the lighter loads show a smaller pressure ring diameter than the hotter loads? Is it that with the hotter loads the case does not tend to spring back, that its ductility has been overridden by the high pressure? Thanks, Rufous.
