The blanks didn't sound as loud to me, either...but that may not be an issue.
I would be inclined to carry only live ammo, giving me the option of putting the first round into the dirt...or the bear, if need be.
Some years ago, I was instructed to always shoot the same gun, with the same ammo: reducing what variables I could, would reduce what liabilities I would encounter after a shooting. This instruction was delivered to me--as an LEO--with the consideration that I might strike an unintended target. In the backcountry, the liabilities are different, but the outcome, not so much...