Yeah. That’s most hunts in Montana. I try to take a trip out to eastern MT once in a while just so I can relax a little bit. I’d be pretty hard pressed if I was relying on a 6.5 anything for ample protection in grizzly country. When I archery hunt I’ll usually carry my 10mm as a sidearm. When rifle hunting my 329PD is the one I’m usually carrying around since I’ll have extra rounds in the rifle too and it’s light. Unless you’re on horseback or darn close to the truck, nobody is carrying around an extra long gun for grizzly protection, yeah a shotgun would be nice to have but carrying one is unrealistic for most people.
If I was the OP, and I intend on it soon, I’d be building a lightweight sheep gun, I want to shoot for the 6-6.5lb range with optics. I’ll carry a pistol too. It’s like you said, when you run into a grizzly, they’re going to be close. A short light handy rifle is going to be easier to swing on a bear if it comes down to that, but in close quarters the pistol is going to be better.
There was a guy that was archery hunting in MT, last year I think, that was charged by a grizzly. The warden that came out marked first blood at 4’ from where he was standing when he took his first shots. FOUR FEET. I don’t want to try to swing a rifle on a bear that’s a mere 48” away, hell, I might have to shove the barrel in his mouth at that point, just to have a chance.
I’d build the sheep rifle and carry a pistol with ammo that you have confidence in.