Some sources say the 9.3x72R uses .376 or .377 bullets, and others say .364 to .366. What's the story?

The .377 is reported by Cartridges of the World and Ken Howell's Custom Cartridges book; Howell's book draws on RCBS and CIP data.

At least one barrel maker and one German load book suggest the smaller diameter bullets are correct.

I saw some CIP numbers once which indicated a larger than average spread between bore and groove diamters, suggesting (to me), it has usually been loaded only with soft lead bullets.

Any one here shoot this cartidge?

The CIP for all 9.3 calibers is .354" bore and .365" groove diameter. These are minimum measurements and an upward tolerance of 0.0012" is allowed. Twist is specified as 1: 14.2" for all.

.377 or thereabouts seems awfully generous and I would not trust that. It is in fact into .375H&H and 376 Steyr territory.

Thanks Gerard. It motivated me to dig out my files on shooting, which had been buried in a recent move. I found my copy of the CIP tables, taken from a German text, from a Nobel book I believe.

I think I may see the source of confusion. The CIP tables give a bore of 0.345 and a groove of 0.364. Oddly, the cartridge diameter just ahead of the the case mouth (ie. the bullet diameter) is given as 0.376 with an equally generous chamber throat at this point. For reference, this dimension on the 9.3x74R is given as 0.366 with chamber at 0.367. All very odd...

10th Ed, COTW, shows 0.365" for 9.3X72R bullets....

I see the editors of CotW have been working. My 9th says 0.376. It's nice to see the work is being kept to date with corrections as needed.