I have bear sprayed grizzlies on 2 different occasions in bc one was young bear probably just away from mom who got too curious when I as fishing and a big boar who followed me and my cuz on our way back to the cabin. Both did not charge so it was pretty effective. But I will add that I always carry a gun and both times a person with me had my .45-70 with the instruction to shoot if the bear moves any closer after I sprayed. Take with you what you can and don't rely on spray alone if you have a gun. A big rifle or shotgun is best. the .44 is better(if you can shoot it) than the 10MM but still not ideal. Take what you feel confident in shooting. Again a big gun does you no good it you can't hit the broad side of a barn with it at the range not to mention with a Gigantic bear charging at you.

The answers from the eastern deer hunters are very entertaining.

Must be lots of expert crackshot marksmen here that could draw and hit a charging grizzly good enough to kill it. I'll stick with bear spray. Last thing I want strapped to my leg is a hand cannon. After the first 1000ft ascend at 8,000ft you'll be wishing you left the handgun at home.

I wouldn't use hollow points for bear you need a good solid or heavy soft point. HSM, Hornady, Buffalo Bore and Grizzly make good ammo.

what about bear spray?

The smallest handgun I would feel comfortable carrying for bear defense is a .45 acp.

I would recommend hardcast bullets, like the ones from Buffalobore 220 gr. Hard Cast - FN (1200 fps/ME 703 ft. lbs.(from their web site) you need penetration, and these guys punch! Hollow points would deflect right off of a big boar grz. head!
I would be carrying my marlin .45-70 with hardcast 430grain as a min.

When I worked in the backcountry in Alaska, we always traveled in pairs. Both carried bear spray and one of the pair always had a Browning 45-70 or 12 gage 870 with slugs. I even carried bear spray and a rifle/shotgun to the privy.

We had to spray bears twice over the three years I was there. All were yearlings, inexperienced, and not showing enough fear. We were never actually charged. But, when they're following and you're backing up, it's a scary scene. I would never shoot a griz unless their was no other choice. They are one of the most incredible animals you'll ever see. As far as a gun, when the rubber hits the road at 25 yards, I can tell you that I'm a much better snap shooter with a long gun than a pistol.

10mm 200fmc @ 1200 = 635 energy factory load

44mag 255ftx @ 1410 = 993 energy Hornady load

good luck with either one.

Stick carry the extra weight and if you are shooting more that 6 rounds then you have a problem besides the gun. Also use a good controlled expansion bullet or lfn, you want the bullet to penetrate and do massive damage all the way not go in 8 in and stop. When it comes to caliber if you can comfortably shot the .44 and are confident in the gun then take it but if you aren't take the 10mm. A smaller gun that you can hit a bear with is alway better than a big gun that you have to literally hit the bear with.

Leave the gun at home and carry bear spray.

If it has to be a handgun, I would go with the S&W .44 Mag. because you would not be likely to get off more than one or two shots at a charging grizzly.

I would leave the bear spray at home. I know I will get a lot of flak on this, but the problem with bear spray is the effective range, 30 40 feet, which is not enough if a big bear is charging you. they can reach speeds over 35mph, can weigh over 600 pounds, and DO NOT STOP ON A DIME! If you wait until they are 30 feet away you might be able to get off a spray shot, but that will only add peeper sauce to the grizzly afternoon snack!don't believe me? try a little role play with one of your friends charging you, and see how long it takes them to stop, now multiply the speed and weight to a bears!

Are you fishing or hiking and just want some protection; because if I were out hunting I would just bring enough rifle and bear spray.

What's with the -1?
I would prefer hollow points to solids because when a bear is charging you he is headlong, so if I have to shoot him I would want to do as much damage as possible.
Dallas, the 10mm has been likened to a .44magnum during ballistics test, however a handgun would not be my first choice for bear protection, especially grizzly.