I read all the posts to this point but will reply as if I haven't... get your Glock (I prefer M1911, but whatever trips your trigger), feed it the best proven 230gr ammo it likes, and hang your food/smellables in bear bags. Worst case, shoving your Glock down a bear's mouth and busting a cap beats shoving your empty fist down his gullet. Bear attacks back East are just not all that likely and almost all the time, if they get your food, that's all they were after anyway - they've evolved into food thieves back east, for the most part.

Anything in a pistol that would be effective on a large predator is not very managable for accurate rapid-fire in a multiple human threat situation - too much recoil to recover from rapidly, even with practice. I can accurately shoot my 44 mag RedHawk pretty rapidly with full-bore 240 gr loads (NOT with 300 gr, though), and it is a very heavy handgun as these things go - one of the heaviest. But I'm a tortise with it compared to my M1911 when it comes to rapid accurate aimed fire.

A 45ACP is a great choice for self-defense but not very good for defense against a predator larger than a cougar. This issue is primarily with bullet weight, not energy. Ordinary pistol cartridges wound and kill via a totally different mechanism than fast rifle bullets. Pistols calibers above 40 caliber efficiently kill large animals all out of proportion to their energy IF they have a heavy enough bullet. But you can't get to large animal lethality with a 45ACP case - overall length restriction, case capacity, and semi-auto design factors for factory ammo defeat you. The real "magic" point with conventional caliber offerings, oddly enough, seems to be 45 caliber, but it starts at around 255gr bullet weight and 1,000fps or so and increases dramtically in lethality as the weights go up about 300 - 350gr on truly large animals. More velocity doesn't seem to add much lethality. As lethal as a heavy bullet 44 mag is, (actually a 43 caliber), it is not as lethal as a heavy bullet 45 Colt load, even when the 45 Colt is loaded to a more moderate velocity. No one can explain that; it's just an observed fact. The uber S&W hunting cartridge, BTW, is actually a 45 caliber, not the 50 S&W - the 460 S&W - althought the 50 is interesting in some respects. These cannons fit my hand very well in the stores, but they are freaking HUGE - I'd rather carry a levergun carbine in 44, 45, or 45-70.

Trying to compare large animal lethality of fast-moving miedium caliber rifle bullets to relatively large caliber heavy bullets is not a logical exercise. You have to refer to ACTUAL results, and then hypothesize to fit reality. Fact is, heavyweight 45 bullets at moderate velocity easily out-penetrate conventional expanding rifle bullets in large game - a well - established fact. And non-expanding rifle bullets below somewhere around 33 - 35 cal usually don't kill as quickly as the large caliber heavy weight pistols bullets (Don't take that as gospel - interpolation was required on my part to work that out).

Having written the above, bears aren't deer or antelope, which I have always found to be extremely predictable to reactions to bullets. In my experiences, black bears USUALLY react fairly predictably to a hit, but every once in a while... a man I knew described his personal horror story to me first hand a year after his recovery from a pretty horrible mauling by a medium-sized blackie that he had shot two arrows through (through!) and then 2 minutes later shot thru-and-thru 5 times with a 454 at point-blank range. The bear died, of course, but much mayhem was committed first. That sort of thing is quite rare with black bears, though.

Grizzly bears seem to be different (Note that my sample size here is more limited; I have only shot 2 and witnessed the taking of several others, but less than 10 total). Regardless of size, they seem to be a bit tougher than blackies and they seem to have a little higher percentage of insanely hard to put down individuals. Every single grizz I took/saw taken reacted differently to lethal hits, so my primary point is that I am not comfortable generalizing about grizzly reactions when shot. One of the bears I saw shot was a fairly large lowland interior animal around 600 - 700 lbs, and it was put down rather efficiently at too-close-for-comfort range with a 44 mag pistol. It did not flip over in its tracks; it kept coming (slowly), but the second shot at 20 feet stopped it and it expired right there in short order. My personal nightmare involves a SMALL grizzly (300 lbs) that I absolutely hammered with a medium caliber rifle - repeatedly. The necropsy revealed that it should have flipped over dead with each shot, but it kept on coming... rapidly. It was closer to me than 20 feet when it finally gave up the ghost - BUT you don't have those in your part of the country.

Get your Glock, stoke it well, and respect the bears who were here before us - best observed from a distance requiring binoculars. They're much cuter at that range...

HTH,

Tom