Neale - do you have the Rem. or the 8x68S?

The recoil is probably identical.

When I chambered up a 9.5x68, I needed to purchase a .375 neck throat reamer to finish the chamber. I'd used a bushed 6.5x68 reamer, plunging it in the appropriate depth for the proper neck length. I no longer have that data.

The reason I bring this up, is that I used .375H&H brass, pushing the shoulder back a whisper, then trimming slightly, not much - that much I remember. I also turned the belts to .522" and had a perfectly fitting base. Upon firing, the case expanded to the proper size, at the web with no problems at all. 2,900fps + with 270's - yeah- we ran it warm. Headspace is, of course, handled by the shoulder and bolt face.

The real point - is the capacity of the .375H&H brass formed to my 9.5x68 was virtually identical to the 8x68S case necked up to 9.5. the recoil will virtually be the same, even if there is a grain or two difference. I am thinking the 8x68X is almost identical to the 8 Rem. Mag.

The 9.5x68 is now a registered round with Huntington Die Service - at least they made a set of dies for it for my buddy, who bought my original rifle, then had another built years later.