Because the Krag chamber is usually a mite oversized, I’ve been sizing BRAND NEW brass using the method that the late Ken Waters recommended with the .303 British cartridge. (SMLE’s  also have notoriously oversized chambers!)
To get the most reloads from BRAND NEW, expensive brass, I expand the neck with a 8mm Mauser “M” die, before sizing down the neck with a .30 necksizer. (Size and try, size and try ‘til the case will finally chamber.) The case now “headspaces” between the “new, auxiliary” shoulder and the bolt face.
This ensures the case head is tight against the boltface when fired.
You still get the expansion ring just ahead of the rim, but there is LESS case stretching in this critical area!
Thereafter, when reloading, ONLY NECK SIZING is recommended! (Make that MANDITORY!)
I’ve been using Ken’s method for years on .303 British and .30 Krag, and am reaping the benefit of much longer case life!