I agree on the choice of 7X65R
It can drop anything in NA (not that I would take it after a brown bear but you have the 400 for that) and any plains game in Africa.
I had a Genossenschaft (guild gun from Ferlach) in 7X65R and it is a wonderful rifle. Traded it for a Honda 250GP bike years ago. Example of priorities at the time I guess.