The deciding factor with 8X57 ammunition is the neck clearance. In some of my "J" (.318') bore 8mm's, a cartridge with an "S" (.323") diameter bullet will not easily chamber. Obviously, forcing such a cartridge into the chamber and firing it could have catastrophic results.

Later model "J" bore rifles have chambers identical to those of the "S" bore rifles, and the larger bullets can be fired in them with impunity. If there is a question, simply determining whether an "S" bore (.323") bullet will slide easily into the mouth of a case fired in the rifle in question will settle the issue.