taken from the CIP drawings
Do these drawings mean anything, though? If Switzerland manufacturered to CIP specs, maybe, but the Swiss are not members of C.I.P. This is their own cartridge and rifles manufactured to their own specification, C.I.P has nothing to do with it.
I do appreciate the link to the K31s slugging out at .305". Like I said, almost all of them I have seen posted are .307" with some .306".