9.3×57mm Mauser

The 9.3×57mm was created by necking up the 7.92×57mm Mauser cartridge. The 9.3×57mm (bullet diameter .365 in.), introduced in 1900, is closely related to the 9×57mm Mauser, even though some dimensions of the cartridge case are slightly different. The 9.3×57mm is still fairly popular among moose hunters in Scandinavia (among hunters in Sweden it is affectionately known as "potatiskastaren", the spud gun, because of the slow and heavy bullet). Factory loaded ammunition with 232 gr and 285 gr bullets is available from Norma of Sweden. The 9.3×57mm Norma factory load with a 232 gr bullet has a muzzle velocity of 2362 ft/s for 2875 ftlbf of energy, which makes it 10-20% more powerful than the 9×57mm.

Usage
It is used for hunting wild boar and moose in Scandinavia. The 9.3 mm bullets (.366" diameter) loaded in this cartridge come in 232 and 286 grain weights.

Reloading
Cartridges of the World listing reloading information for both the 232 and 286gr bullets using IMR3031 powder as well as showing a Norma factory load.

The loads listed in Cartridges of the World are valid, but dated. The loading information has not been updated to reflect newer powders than IMR 3031. My research indicates IMR 4064, Norma 203 and Reloader 15 are all suitable in the same ranges as IMR 3031. As always, be cautious and start low. You are on your own!