Lol Phil S. stole my handle! When I tried setting up an account a few years ago on AR it said it was already taken. Didn’t know by who until a couple years ago.
Anyhow the grizz was 60 yrds and Barnes 270gr TSX. I was actually after a caribou when I saw the bear. Much prefer the nosler accubond. The TSX just drive through and don’t do much, better for the meat department. For bears something that expands easier is better. Going in willows after a bear is always interesting and not for the faint of heart.
Shot placement is key. Bears are easy to kill if you put the first shot where it needs to go. Screw up the first one then it’s a tumbling, rolling, hauling donkey mess that’s difficult to actually put a round where it needs to go.
To answer the OP go with the 300 weatherby. Accubonds are what I prefer. Even a big blackie isn’t very big boned so you want something to expand but hold together. if you see one at 2-300 your still in business.
I find it funny when some people think, one needs a super large caliber to drop a black bear. I've killed a fair share of Black bears in the last 45 years weighing anywhere from 180 lbs' / 475 lbs + using nothing more then a 308 caliber soft point bullet. It's not so much the caliber, but most importantly the shot placement. But for the faint of heart use what ever you feel comfortable with, there is no such thing as overkill, Dead is Dead.