Imagine stabbing someone with a 1" dowel. Might hurt, probably not going to penetrate. Apply the same force to an ice pick and it will definitely penetrate. Just a matter of surface area the force is applied to.

So I got to wondering, vis-a-vis shooting bears in the head. Seems like it is not just the sectional density of the bullet that would count, to penetrate the skull is a combination of the muzzle energy and the surface area that muzzle energy is spread over. Is it possible that a 357 might have an advantage because it focuses it's energy on a smaller area, thus being more likely to penetrate the skull?

Decided to calculate "Muzzle energy per square inch" that a specific ME and caliber yields. Here's a few numbers in descending order.

12980 30 Carbine, 110g FMJ @ 1990fps
10604 Buffalo Bore 44M +P+ Outdoorsman
6768 Buffalo Bore 357 Outdoorsman
6413 12ga 437g slug @ 1800fps
3696 Buffalo Bore 38Sp Outdoorsman, from 2" bll

I find it interesting that the carbine rates so high and the 12ga so low.

My bear in the woods load is PPU 300gr. FPSP. 44 Magnum. I have never seen a bear in the woods and if needed, I hope it works.

Muzzle energy is NOT the key value. The important value is momentum, Mass X velocity. Ammo makers used to advertise that value but Kinetic Energy is flashier and sells more bullets. KE can be burned off in heat, sound, noise, in addition to tissue damage; any kind of energy loss. Momentum is conserved. Redo those figures in terms of momentum per surface area and you will see what you would expect.

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Kind regards, Heinz

Having tons of experience shooting deer with 1oz 12ga slugs, I would think the slug would shatter the skull rather than penetrate straight through like a smaller bullet.

My question is, is the bear pooping in the woods at the time of said shooting. And if this is the case, why are you shooting a bear that is pooping in said woods, it is not hurting you. My advice would be to leave bears in the woods that are pooping.......or not pooping. Just leave them alone. If you disturbed said bear that was pooping in said woods and absolutely have to shoot the bear then I would do what Bella Twin did and used a 22 and shoot it in the head multiple times. Just make sure you hit it in the right place.

I think that you don't understand what sectional density is. It IS a comparison of momentum to the surface area over which it is applied. Note that momentum is used rather than energy.

Oops. It is a comparison of MASS to the surface area over which it is applied. Multiply by velocity to get momentum.

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Formerly Model520Fan

I see his point, a larger bullet has less of a chance of penetrating. If the larger bullet bounces off and the smaller one penetrates regardless of momentum, which one will be more effective?

But then again, the higher momentum may have a greater chance of busting thru.

Use blocks of wood or metal plates of different thicknesses. Shoot with .357M and .44M having the same speed and see which has the best penetration. Larry

About all I can add to this is that Karamojo Bell killed a bunch of elephants in Africa with a 7mm. Says a lot for sectional density.

Says a lot for his shooting ability.

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Kind regards, Heinz

Buy some skulls, maybe fill them with a gelatin to simulate brain tissue, and experiment away.

Black Bear Skulls for sale by www.hideandfur.com

I understand this is really a hypothetical conversation starter and I’m all for it.

Data can be manipulated to infer various outcomes and it can be fun and interesting to discuss taken within context.
I’ve only seen two bears in my life and both were black bears minding their own business at a distance
Having said that, if I ever were to hypothetically find myself in the position of having to stop a charging jaw popping Grizzly Bear I would want something more than a 30 carbine.
If anyone wishes to go out and attempt to stop a charging jaw popping grizzly bear with a 30 carbine I guess they can.
I’d even go as far as to say they would have the rest of their life to prove that it would work

Numbers are numbers.

Actual shootings are facts.

I don't go hunting bear with a 1.21 Caliber, ping pong gun !!

My Buddy Milt had trouble shooting a treed bear with 357 Win Silvertips.
Not much penetration!

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NRA LIFE MEMBER

The .30 Carbine would just bounce off the skull.

It lacks power and sectional density.

The key factor for the rest of your choices is bullet construction.

The .44 Magnum with a strongly constructed bullet is your best bet.

If you want to go shotgun........the slug would probably be too soft to be effective.

If you want effective shotgun........use #6 shot.

It will take out the eyes and nose and the bear will be unable to find you.

Folks in Alaska are reported to favor the Brenneke Slug.
When you see an Alaskan Game Warden or LE go into the bush where there may be bears they are usually carrying a Shotgun.
I have shot Deer with the old school American Slug which appeared to be pretty soft, pure lead or close to it.

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NRA LIFE MEMBER

I've read plenty of accounts of penetration, lethality, and shot placement. As noted above with the ".275 Rigby" --- better known as the 7mm Mauser --- shot placement is still king. The shoulder busters give you better lethality on an imperfect shot, but there's still no substitute for hitting the CNS. Alaskan Natives regularly take polar bear with .223s, for example. I wonder what they think of everyone else and their semi 12g slug guns, .375s, and .44 snubs?

Not to divert into politically incorrect territory, but as a man of European descent I note a tendency of those from that continent who hunt outside the homeland to pack far more 'gun' than the more pragmatic (or simply poorer) locals. Heard tales of missionaries and others in Africa who are amazed at what the locals take with .22LR because it is all they can afford to shoot.

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Psalm 27:2

.357 Magnum bear load? Maybe, it’s a bit too hot for medium-frame revolvers currently.

Read about Bella Twin and her grizzly-bear takedown with a single aimed shot with a .22 Long, plus a few more rounds for good measure.

Attached Images

D69CBD83-6A2C-43A6-9148-D3837AB5869D.jpg (67.8 KB, 26 views)

There are actually videos of this on YouTube. Guy. Ompares a 44mag to 10mm for brown bear skull penetration. Whole thing is silly. It’s a dried out bleached skull. No skin, no muscle. I can’t speak to polar, brown or grizzly bears but killing a black bear is not that difficult in my experience. While I haven’t done it I would think a good FMJ in most self defense calibers (9mm and up) would penetrate a black bear skull. Grizzly skull might subject bullet to a ricochet effect because of shape. Hope I never have to find out.

Brenneke didn't do real great on penetration in this test.

It is a lot better than the old school rifled slug though.

Okay, let's settle this once and for all. Anyone who has shot two grizzlies in the head at close range, one with a tiny bullet and one with a fat one, raise your hand and tell us which worked best. The rest of you, pipe down ...

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Pisgah

Lmao!!!!! Best post of the week

Naw.........such anecdotal experience proves nothing.

We'd need a controlled peer reviewed study of at least 300 dead bears.

Use the same type and hardness bullet. I use Oregon Laser Cast 158 SWC and 240 SWC. Both bullets going over 1400 FPS. The .357M will go through one side of a 20 lb. propane tank but the 44M goes through both sides. That leads me to believe that the theory that the smaller dia. will penetrate more is false. Larry

And his running ability.

Looks like the 10mm with heavy cast bullets is the go to hand gun up in Alaska. A lot of people carry a 44 Magnum along as backup.

I had a bear in the drive way when I came home one night. I started carrying my 44 Magnum when I walked the dog after that.

In addition to bullet weight, velocity, caliber, and SD, bullet shape makes a difference in penetration. Most people think a pointy bullet means deeper penetration, but testing has proven bullets with a flattened nose tend to penetrate in a straighter line than pointy or round nosed bullets, less likely to deflect and change direction (veer from the intended aiming point). That's why many newer FMG big game rifle bullets have flat noses. They penetrate deep and straight.

In actuality, any of the bullets listed by the OP will kill a black bear with a head shot.

Larry

What, pray tell, is the peer of 300 dead bears?

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Formerly Model520Fan

Are we talking Alaskan grizzlies, or Chicago defensive linemen, or a scrawny kicker?

I'm talking GRIZ.

I don't pretend to know what others are talking about.

This can be analyzed to the tenth degree with charts, graphs and 8x10 glossies. When we are done, there will be one thing that has always been true, and will always remain true. I matters not whether it travels on two legs, four legs, swims or flies. If it gets hit anywhere near a vital spot with one ounce of pure lead traveling at 1700 fps (the specs on my box of Winchester 12 ga slugs) it is going to die.

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NRA Life Member

OP here, thanks to everyone - was hoping I'd learn something and I did. The practical answer is probably, while a smaller projectile does focus the force more, a heavier projectile will have more force and so it's a trade-off (like everything else).

Now headed out back, 357 and 44 in hands, patiently waiting for 2 twin bears to attack at identical pressure/altitude specs...

Just so your slug is better than this one. I doubt that it would do anything deadly against the skull of a grizzly bear.

It looks to be far too soft. Griz might have a headache while crunching your bones as he finished his lunch (you).

Does the caliber REALLY MATTER?

Or is placement what Really Matters?

Clipped from internet.

"Attempting to scare off a grizzly bear with a gunshot turned out to be a costly mistake for a Casper man, as the round from his . 22 caliber rifle wound up killing the animal. In Park County Circuit Court in November, Brent Stalkup, 38, pleaded guilty to a misdemeanor count of taking a grizzly without a license."

The fine was $25,000 which I find to be outlandish for this event.

I personally know a man who shot and killed 2 relative small black bears in Idaho 45 years ago with a 22lr rifle in the eyes area, I guess the skull is thin there.

I know of another man who intentionally shot a bear in the nose with a 22lr which did make the critter leave his camp area.

Personally, I would do neither of these things, with my luck it would really pissoff the bear and I would be served to his friends and family at his dinner table.

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Who are? "They"

Yes.........with the .22 the placement must be perfect.

So perfect that it's mostly a matter of luck........bad luck if you didn't intend to kill the bear and the game warden nails you.

Large calibers like the .458 Winchester give you a little more leeway.

They also make more noise so the game warden is more likely to hear you and spoil your fun day.

Figure I would be carrying either the 45.70 (430gr) or 44mag (265gr) rifle both using flat nose rounds with the 10mm on body with 190gr flat nose. If they doesn't work then maybe the odor will drive them away

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Is that a gun No a lifesaver

If that doesn’t work , it wasn’t meant to be. When your time is up. Your time is up.

This seem to me to be that best study of what has actually worked in the real world. 93 cases. Multiple calibers. 97% success rate.

Update: Handgun or Pistol Against Bear Attack: 93 cases, 97% Effective

For me, the takeaway is: use the gun YOU can get multiple hits quickly with and load it with something that penetrates. No need to overthink it. You're not engaging in sport hunting.

There are solid copper slugs, and heavy jacketed slugs as well, or even steel sabot rounds. A riot shotgun with a load of slugs is likely your best bet. A Shockwave in a back holster you pull over your shoulder and fire quickly (assuming you aren't wearing a pack) might be a smart idea.

Glock 20 or 40 with heavy hard cast 10mm are popular as well.