Cool Rifle-
The 8x50 and 8x56 both need a faster powder that 7828, just a Corbin says. The other end of the spectrum is 3031- probably too fast. A powder in the range of the mediums of Varget, 4895 H4350, all Hodgdon powders, or 4064, 4320, 4350 in IMR cans will probably work the best.
: In working up loads, any load you can use with 3031 in your 8x56R, can be used with the slower powders, then work you way up as pressure signs and recorded velocities indicate.
: A just gave a couple clips of 8x68R ammo to a friend who just picked up a simlar rifle, but probably full military. They ammo was loaded with .328" bullets by the way, not .323". His rifle's groove diameter is also .328". He is not considering buying a custom mould to cast the correct size heavy bullets for his rifle.
: I suggest you slug the bore to find the proper diameter.