Originally Posted by ghostdncr
My realistic choice for that environment? A 590A1 Mossberg loaded with 2 3/4" high-brass #00 buck. Multiple instantaneous hits will flat disconnect the CNS and require a complete reboot. By the time the system comes back on, hypovolemic shock has set in and, well, game over.
There's my $.02
I have to disagree with you ghostdncr - shooting buckshot at a large bear sounds like a great recipe for the bear eating "hunter du jour".
Buckshot is usually made from soft lead pellets, and even when coated, the coating is just a thin layer of copper or nickel to avoid damaging the pellets while traveling through the barrel of the shotgun. 00 Buck is only .33 caliber - so the net result would be shooting a heavily muscled bear 9 to 12 times with a .32 ACP loaded with soft lead balls (e.g. - not even as hard as a normal FMJ). Granted you would probably get several hits, but would they penetrate enough to either break bone, damage organs or penetrate enough to disrupt the CNS? Highly doubtful. Would they stop the bear? "Good Luck!"
I will stick with my original recomendation, a 12 gauge shotgun with 1-1/4 oz hard cast slugs (like the Brenneke Black Magic) either 2-3/4" or 3" shells. Actually, I recommend the 2-3/4" shells to make sure you do not accidently short-stroke the pump before the hull clears the receiver and causes a jam. Only use the 3" shotshells if you have a gun with either a 3-1/2 chamber (has a longer ejection port) or with a gun that has had the ejection port relieved for additional hull clearance.
BTW - my friend further modified his carry gun for Yellowstone, a Mossberg 500 with a 16" cyl barrel, then installed a synthetic pistol grip on both receiver and fore-end. Net weight less than 5 lbs, carried on a cross shoulder sling. I got to test fire it with a full power 1oz deer slug, recoil was stiff, but definitely manageable.