9mm vs 10mm for Bear defense.

[Dave0317]

This debate has a lot of parallels with the current trend of smaller rifle calibers for big game.

Less recoil generally results in more accurate shooting.

Plenty of small handgun calibers have the penetration capability to hit CNS on any bear.

More shots and less recoil, means more likelihood of hitting CNS sooner.

The reliability debate is honestly just comical to hear in 2025. If a revolver were more reliable, you would see them being used at police departments, military units, and other people that dont just carry for a chance encounter, but specifically and intentionally put themselves in danger on a regular basis.


As far as the non-CNS shots and warning shot type situations, I think a lot goes unreported, so there is not accurate stats on that. If a bear is curious and gets too close for comfort, a warning shot might actually work, and if there is no blood drawn, is there a requirement to report that to the local wildlife people? Likely not in many places.

The emphasis on CNS hits is because that’s the only thing that is an immediate stop. We all know a deer can run up to 75 yards even with a disintegrated heart and lungs. The military and police world refers to this as timers and switches. CNS is an off switch. A determined bear shot in a lung, may still close distance and maul a person before its brain finally times out due to blood/oxygen loss.

 

[z987k]

This debate has a lot of parallels with the current trend of smaller rifle calibers for big game.

Less recoil generally results in more accurate shooting.

Plenty of small handgun calibers have the penetration capability to hit CNS on any bear.

More shots and less recoil, means more likelihood of hitting CNS sooner.

The reliability debate is honestly just comical to hear in 2025. If a revolver were more reliable, you would see them being used at police departments, military units, and other people that dont just carry for a chance encounter, but specifically and intentionally put themselves in danger on a regular basis.


As far as the non-CNS shots and warning shot type situations, I think a lot goes unreported, so there is not accurate stats on that. If a bear is curious and gets too close for comfort, a warning shot might actually work, and if there is no blood drawn, is there a requirement to report that to the local wildlife people? Likely not in many places.

The emphasis on CNS hits is because that’s the only thing that is an immediate stop. We all know a deer can run up to 75 yards even with a disintegrated heart and lungs. The military and police world refers to this as timers and switches. CNS is an off switch. A determined bear shot in a lung, may still close distance and maul a person before its brain finally times out due to blood/oxygen loss.

And just like the small caliber debate, the bullet matters a lot more than the headstamp. I'd rather have a 9mm with leighigh extreme penetrators than a 10mm with hollow points.

 

[PredatorSlayer]

I hunt in grizzly country all the time and have been carrying my Glock 29 for the last 10 years. The best argument I have heard for a wheel gun is that if things get close and personal and you have to shove the gun into the bear because it is on top of you, the semi auto will likely fail because the slide might not close all the way. A wheel gun you can keep pulling the trigger and it will go bang. Caliber/cartridge aside, I think one of those 8 round 357s look like a decent option that I am going to explore.

 

[rclouse79]

I currently have a Glock 10mm, but am thinking about trading it or selling it and getting a 9mm or .57. I am leaning more towards the 9 due to cheaper ammo. If I actually practiced with it, it might actually be useful in a pinch.

 

[pacoalcracker]

I'm in the G19 9mm camp with 147gr HC Outdoorsman +p. However, I would not overlook the 10mm G40 with a 200gr HC if a bit more weight and a bit longer slide is tolerable since it makes it less flippy and more accurate with the longer sight radius and has a bit more power. I shoot both and don't see much if any difference in getting and staying on target. However, the 9mm has more shots available and is my 1st choice.

Revolvers are and always will be more reliable than any semi-auto. LEO don't carry them simply because the semi-auto holds more rounds and can be reloaded much quicker.

Hard Cast bullets are considered "expanding" and are legal in all states except those with a ban on lead projectiles.

 

[Sdvldog1371]

So, a range buddy who has been trying to sell me on 10mm since I met him decided to shoot a Black Bear this year while elk hunting. He smacked the bear at a fair distance with his .308 win using 195 TMKs. He hit her square in the boiler room. She took off and he hit her twice more. She got down into a deep ravine and wasn't having any people in that ravine. They tracked her the next day and find her hold up in a tight spot. He said she sounded pretty rough, he pulled his 10mm and shot her in the head...she took off. He mag dumped her with a total of 3 to the head...1 through and through...and his hunting group shot her several times with rifles before she gave up the ghost. If you're in a life or death with a bear...best you make good with your maker unless you're carrying something that is going to remove its head.

By the way, he has a super fancy, super expensive 10mm pistol he's making payments on to be built and he's thinking of going another direction. He was a huge 10mm fan. Just saying.

 

[mtblackdog]

I live in, work in, hunt in the heart of Montana Grizzly country. I carry my Glock 20 anytime Im outdoors with extreme penetrators. Its hella accurate and controllable. But if I can I carry a 45/70 as well. I hate to have to rely on the 10mm but sometimes a long gun like during bowhunting is just not an option. Id wouldnt even consider a 9mm for myself. Im seriously thinking about getting a 460 and suffering through the weight. Grizzlies are no damn joke and thick as thieves here. I could tell story after story on how truly dangerous they are.