If a .323" bullet will slide easily into the mouth of an unsized fired case, you can continue to fire .323" bullets with no concern about excess pressure.
Usually chambers of older rifles cut exclusively for the 8X57J (.318 bullet)cartridge will not accept a cartridge loaded with a .323" bullet. My pre-War Sauer drilling in caliber 8X57JR will not accept an 8X57JRS cartridge in the chamber.
If one does, it is usually an indication that the chamber was cut that way intentionally to allow the use of either cartridge.
After new regulations were issued in the early 1930's, all Germsn 8X57 chambers were cut the same size, irrespective of the size of the bore,
