You need a .22 to survive a bear attack. You use the gun to kneecap the other guy. You only have to be faster than one person. Other than that, when I was in Alaska I flew in a Cessna 152 and 172 with a Ruger Redhawk .44 Mag (7.5-inch barrel) strapped to me in a shoulder holster (hip carry was out of the question) in summer and winter. It proved to be almost more annoying than not having a gun at all. It was bulky and got in the way of everything. I would switch to a Super Blackhawk in the same caliber/barrel as the dimensions are a little more manageable. Maybe go with the shorter barrel.

YMMV

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My $.02