I like the ruger Redhawks Alaskan in 454 for all the same reasons, except, center mass aim point with a handloaded, 410 grain wide flatness gas check at 1400 feet per sec. Should only need one shot. Alas, in Michigan we have black bear, no grizzly.
Is “center mass” on a Griz an INSTANT kill shot?
If it takes him more than 30 seconds to die, you’re already half et.....