It all depends on what you consider dngerous gme. I usa a 300 WSM for everything i hunt. But ihave never hunted Grizzley or Brown Bears. For them i would go with a 338 Mag minimum but would like to go for a 338 Ultra Mag or 338 Laupua Ma for them. Ive also never hunted in Africa for anything but if i was going to a 375 H&H would be a minimum for dangerous game there but i would prefer atleast a 416 Rigby. Some people around here consider black bear dangerous game. I know people that have killed them with a 25-06 and 270.