My long-held contention (just unwilling to do the research) is that more bears have been killed by the .30-06 then the the next 2 or 3 cartridges combined.
I have a cold Pepsi for anyone that can prove me wrong.
I can't prove it but the .30-30 can't be far behind.
IIRC Hosea Sarber was a government hunter in Alaska and killed stacks of brown bears with his preferred caliber, the .270W.
"Be sure you're right. Then go ahead." Fess Parker as Davy Crockett