Is there not a chance that it is a 9x72. I had one of those (and the 9.3 would not chamber). Still have the loading dies and about a hundred rounds of new brass I might be persuaded to part with. The 9x72 does not have a bottleneck. Interestingly, the Sellier and Bellot ammo marked 9.3x72 mics out to 358 on the bullet--pull one and see! Maybe they were concerned about the occasional narrower bore out there. (Of course you COULD just double your money on the gun with me...) Steve