Not to argue with my betters,I suspect the head diameter of the 8X50R would be larger than appropriate.I would suspect something based on the 360 case, although this can only be a guess w/o some dimensions.This can be verified or refuted by simply measuring the chamber dia. at the head, or either the rim dia.Some type chambercast would still be required to ID the specific cartridge within the 8mm family of cartridges.
Mike