That has been on my rifle list for some time. Unfortunately they show up only infrequently, and then usually in the Ackley version for some kind of long range shooting, with a heavy barrel.
There must be some other cartridge that is a stand-in. The 8s and 8.5s The 35 Whelen, 8.5x63, and the 338 Win Mag. An argument can be made that the latter is the best hunting cartridge for Brown Bears (as opposed to a stopping cartridge), So that would tend to cover you up to 1000 pounds. One could argue that the 338 bullets out there are designed for the higher velocities of the mag and Weatherby. That might work to your advantage because in the African world a slightly tougher bullet, the effect of shooting it at 06 case velocities, could be a good thing.
Stuff tends to perform within it's specs unless one crosses over into a different theory set, such as is present with something like the 6.5 C., or even with much earlier 6.5x55. But so long as everything just scales up and down, you get what the numbers imply, so long as one takes the functioning of individual bullets into account.
