If you are considering original chamberings, don't overlook 8X64S, an original Brenneke cartridge, and far superior to the 8X60S in case capacity and performance. Cases can also be formed from .30-'06 brass. I have a Husqvarna Mauser 98 sporter in 8X57S I will be converting to 8X64S as soon as I can find someone with a chamber reamer to do the job for me.

One possible problem for me is that the neck dimensions on my 8X57S are larger than the neck dimensions given for the 8X64S, but since the shoulder of the 8X64S is 55mm from the base of the case, that only leaves a 2mm section of the shoulder which would not be cleaned up. Or I could have the chamber cut using a 7X64 reamer with an 8mm pilot and use an appropriately sized necker and throater to cut the neck and throat.