I recently bought a Type B Oberndorf Mauser in 8 x 60 caliber which has been 'renumbered'. The original Mauser serial numbers on the receiver and barrel have been ground off and replaced with a new 6 digit number. The bolt number doesn't match the new number and the bottom metal looks like it may be from a military action (has lock screws in the TG, but also has lever floorplate release). The rear sling swivel is missing. The receiver has the original 8 x 60 Mauser caliber markings and BUGN proofs. I am trying to figure out whether this rifle takes the 8x60 (.318) cartridge or the 8x60S (.323). I'd be grateful if anyone could shed any light on this. I've attached photos of the original mauser markings under the barrel. Also, does anyone know anything about the practice of renumbering rifles, why it was done, etc.? (this one comes from S. Africa I believe).

thanks for your help and I really enjoy the forum.

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