I have a M1917 in Military Configuration. It has a bit of excessive Headspace. I took new brass and sized it down in a LYMAN 310 neck size die. I keep turning the die down until it bulged the case shoulder so the case was wedged tight against the bolt face. Then loaded them with a minimum charge of IMR4350 under a Sierra 150gr Spitzer BT.
The case was fire formed to the chamber with no stretching. I readjusted the 310 Neck Size die to just size the top 3/4 of the neck.
I've shot these cases with the same load of a Sierra 150gr SPBT, over a light charge of IMR4350. At least 12 reloadings, no case stretch, trimmed once. Just kept separated from all other .30-06 brass.
Ya just got to know how to do all the little tricks.