I know nothing about grizzly bears however if you were in this area would you not have had a large bore pistol on your belt? I don't understand the throwing the pistol either, I would like to think I would have fired the pistol at the bear instead of throwing it to the man being killed if I read it correctly. I don't think I would want a 10mm in this case based on the black bear that took 14 or so 10mm rounds and still chewed the guy up pretty bad. I don't know what he had for cartridges though.