There have been two serious maulings in the lower-48 involving Grizzlies. One was outside the West entrance to
Glacier NP, involving a US Forest Svc LawEnf officer on a mtn bike. The other was in the Wind River Range
NE of Yellowstone.
Guide and hunter returned to bull elk claimed by sow grizzly the night before. A Glock pistol (unk caliber)
was carried by them, but thrown short by hunter to guiode.
Bears are fast and unpredictable. I carry a 450 Alaskan on a pre-war Model 71.
Either a heavy revolver or auto is a good idea, with spray.
Bears of all types can be dangerous if surprised or threatened over claimed fish or game.
Just two? What time frame?