.45 ACP For Bear Protection: Everything You Need To Know

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As more people participate in outdoor activities, contact between bears and people has increased. Two types of bears occur commonly in numerous states of the US and Canada, the Brown and Black Bears.

The brown bear, known commonly as the Grizzly, has gained legendary status over time due to its massive size, power, and undoubtedly its cuddly appearance.

The .45 ACP is not the best caliber for a bear protection gun. The caliber lacks the penetration and power required to stop a bear in its tracks reliably. The .45 ACP is, however, not a slouch and can be turned into a perfect bear gun, provided that +P loads are loaded with 255gr hard cast bullets.

For most of us, it’s just not worth the cost to buy a dedicated bear gun unless you spend a lot of your days in the woods. It makes perfect sense to carry your trusted sidearm should you find yourself in a confrontation with a bear.

Should your pistol be a .45 ACP, it would indeed have crossed your mind if it is enough gun to save your bacon reliably. Let’s explore the options together.

.45 ACP For Bear Protection

.45 ACP For Bear Protection

Brown and black bears are massive animals, growing up to seven hundred and five hundred and fifty pounds, respectively. They have thick skins covered in rough hair, thick necks and shoulders, and big solid heads. In a one-on-one altercation, a human stands little chance of escape.

Bears are primarily hunted using high powered heavy-caliber rifles that penetrate deeply and deliver the energy required to put down any bear from the most reasonable angles reliably. Worldwide an average of thirty bear attacks occur annually. About eleven occur in North America, with about a third being fatal.

In the bigger picture, this number is minimal compared to the millions of people who venture into the outdoors annually. Some areas, of course, have higher bear populations than others. Should you find yourself in such an area, it is a good idea to be armed adequately to reduce the risk of becoming the following bear attack statistic.

The .45 ACP cartridge has all but reached legendary status amongst firearm enthusiasts and movie addicts alike. The legendary Colt 1911, M1911, or Colt Government as they’re referred to brought their popularity to the fore.

Today we naturally have many different types of pistols made in the caliber, which has further fueled the popularity of the caliber. A two hundred and thirty-grain hollow point bullet striking an assailant pretty much anywhere in the torso will result in swift incapacitation. As a self-defense caliber, the .45 ACP stands back for no one.

Many outdoor enthusiasts are owners of .45 ACP chambered pistols, and it is natural to assume that it can get the job done against bears, given the large hole at the end of the muzzle. That is the crux of this article. Can a .45 ACP be relied upon to stop a bear if you need to shoot in self-defense?

What Handguns Did Our Forefathers Use On Bears?

Before the advent of modern propellents and self-contained cartridges, the old frontiersmen and homesteaders were reliant primarily on military weapons that ended up in civilian hands in some way. Old black powder can and ball and later on, basic self-contained cartridge revolvers were pretty much what was out there.

Calibers mostly ranged from .36 to .44 inch diameter bullets, all made of lead. The list below lists the handguns available from about the eighteen forties to nineteen hundred.

Make (Revolver)Cartridge typeCaliber (Inch)Manufacture Date
Colt PattersonCap & Ball.361838
Colt WalkerCap & Ball.441847
Colt NavyMetallic.381851
Colt DragoonCap & Ball.44 (.454)1848
Colt ArmyMetallic.441860
Smith & Wesson Mod3Metallic.441870
Colt Single Action ArmyMetallic.45 Colt @ 44-401873
Remington New Mod 1875Metallic.45 Colt, .45 Rem, .44 Win1875
Colt Double ActionMetallic.32 Colt, .38 Colt, .41 Colt1877
Colt New Army & NavyMetallic.38 Long Colt1892

As can be seen, Colt dominated during this period. Most revolvers were chambered for the .44 diameter bullet. Most weighed around 220 grains and traveled at seven hundred to eight hundred feet per second. Compare this to the modern-day .45 ACP, 230gr bullet velocities; we end up at an average of between eight fifty and nine hundred feet per second.

The old frontiersmen undoubtedly had to deal with bears using their revolver. None of the old black powder revolvers were designed for such duty, but it is all they had.

Given that we have better ammunition choices and can custom load ammunition to our requirements, we’re much better equipped than our forefathers to deal with bears.

How Popular Is The .45 ACP As A Defence Against Bears

In my research, I came across four bear attack incidents within the last ten years in the United States, where the potential victim was armed with a .45 ACP. All four incidents ended in the shooter surviving and dispatching the bear.

The bear sow had two cubs that she defended and weighed four hundred pounds. Only one incident mentions specific detail, and ammo used was a .45 ACP 230gr Full Metal Jacket, shot out of a six-inch Glock. Amazingly, it took three volleys of three shots each, fired into the shoulder area of the bear to stop the charge.

The other three bear attack incidents also required multiple shots fired from a .45 ACP per bear to stop the charge.

How Deep Will The .45 ACP Penetrate On Large Animals Like Bears?

The .45 ACP cartridge was specifically designed for use against human beings. Humans are significantly less tough or robustly built than large animals such as bears. Most .45 ACP hollow-point bullets penetrate between fifteen to twenty inches of ballistic gel, closely resembling human tissue.

Theoretically, this penetration level enables the .45 ACP to pass through the human torso and disable a second person. Penetration, of course, depends on what resistance in the form of bones the bullet encounters along the way.

Bears are significantly larger than humans, have a course hairy coat, thick skins, large skeletal structure, and a hard slanted skull. Shooting a bear from the side into the vital area, where only a rib would be encountered, would no doubt eventually bring down the bear, even if only one lung was punctured.

The problem comes in when the bear faces you head-on; the brain is a tiny target to hit as the nose, muzzle, and jaw structure cover most of the brain and brain stem. Add to this a nearly two-inch forehead and skull that needs to be penetrated to reach the brain. The hollow-points success rate in achieving this penetration would be pretty low.

Ignoring the bear’s head, the only other shot to take would be to shoot centrally into the chest just below the chin. The hope here is to reach the heart-lung area without hitting a heavy bone.

Twenty-odd inches of penetration is about the minimum you’d be getting. Bears, however, have very thick skins and fur around the neck area that will limit a hollow-points penetration significantly.

A shot to the shoulder or the upper leg area may well break a bone, but there’s no guarantee that this would turn a brown bear. Deep penetration is needed to reach the bear’s vitals.  

Best Choice Of Ammo For Bear Defence

The average 230 grain .45 ACP bullet is launched at about eight hundred and fifty feet per second, which is pretty mundane by today’s standards. The bullet diameter is .452 inches for jacketed bullets and .4530 for lead.

The short and stubby-looking bullet is impressive to see but lacks the velocity required to penetrate adequately on a bear in standard factory form. Let’s look at ways to enhance the .45 ACPs performance to reach the vitals of a giant bear reliably.

Other than replacing your .45 ACP with a dedicated bear gun, the obvious choice is to improve the performance of the bullets that we use. Expanding bullets give up too much energy and penetration during the expansion process, which is not ideal.

The next logical step is to consider Full Metal Jacket bullets that penetrate deeper into a target than hollow points do. FMJ bullets have a downside in that they penetrate well but don’t inflict the same damage as a hollow point, nor do they penetrate deep enough to reach the bear’s vital organs.

To illustrate the point. I know two people that were shot in the belly with 9mm Parabellum FMJ’s, and both survived without any internal damage. The round bullet head simply pushed all the internal organs and arteries out the way and exited without needing more than a stitch or two each to close up the wounds.

So it’s a case of the best for last. Given that bear attacks happen at close range, we don’t need a long-range bullet. What we need is a bullet that stays on course, penetrates deeply, cuts a proper wound channel to ensure the bear bleeds out quickly if not dropped dead, and lastly won’t ricochet off the bear’s skull. A tall order, I know, but the solution is at hand.

The heavy for caliber Buffalo Bore Outdoorsman 255gr Flat nosed hard cast ammunition is as close to perfect for the purpose as what you’re likely to find. Traveling at 925fps and delivering 484ft-lbs of energy, this bullet brings the .45 ACP back into the game as a reliable bear stopper.

Penetration tests conducted in clear ballistic gel produced astounding penetration results. Remember that hollow-point ammo seldom passes the twenty-inch penetration mark when shot into a gel. The 255gr Buffalo Bore +P ammo exceeded fifty inches of penetration. Enough to make a brown bear change its mind when charging.

The buffalo Bore bullet has a flat nose which aids the bullet to cut its way through fur, fat, flesh, and bone and keeps the bullet on a straight path. The flat point also vastly reduces the odds of the bullet ricocheting off a bear’s skull even when striking it at an angle.

Even when striking bone, the hard cast lead will keep its shape far better than other .45 ACP lead bullets. The additional weights of the head at 255 grains, combined with the increased velocity, results in increased momentum, which in turn results in great penetration.

Which .45 ACP Pistol Is Best For Outdoors Carry

Are .45 ACP Hollow Points Any Good For Bears?

A hollow-point bullet placed into the chest area of black bears will stop a charge. Black bears are susceptible to pain and are easily deterred from pressing through a charge if hit with a substantial caliber. Their aggression levels overall seem lower than that of the brown bears.

A brown bear’s motherly instinct is not to be taken lightly. Brown bears, Grizzlys, or Codiac bears have a meaner temperament. Once they decide that they don’t like you, you’re in trouble. Especially so when you bump a sow with cubs.

Regardless of the caliber, Hollow-point bullets are designed to expand on impact to create a more effective wound channel and do as much damage as possible while rotating like an airplane’s propeller along the wound channel.

Fired hollow points have the classic mushroom shape once expanded. The expansion, however, comes at the cost of penetration. A solid or full metal jacket bullet of the same weight and make as a hollow point will penetrate deeper than a hollow point but will cause minor damage along its path.

Modern expanding bullets are virtually guaranteed to expand, which is excellent when challenging a human perpetrator but less than ideal when confronted with a seven hundred pound bear intent on killing you.

Ideally, you’d want a caliber that can shoot straight through the bear from any angle, giving you the best odds of hitting a debilitating organ. Hopefully, it will also break a few bones along the way, incapacitating the bear and preventing it from getting its claws and teeth into you.

Under normal conditions, a .45 ACP at a point-blank range can knock a bear over if the brain or spinal cord is hit. Now picture a bear lumbering towards you at 40mph with its head bobbing up and down as it gaits. These are hardly ideal conditions conducive to accurate shot placement.

Realistically all you can do is shoot for the center of mass and hope a bullet strikes a debilitating organ. In such a situation, you need to have a bullet capable of penetrating deeply. The hollow point bullets penetrate only fifteen to 20 inches in the .45 ACP caliber, which is hardly enough to stop a bear given its bulk.

Which .45 ACP Pistol Is Best For Outdoors Carry?

When considering a pistol for outdoors carry, carrying convenience is a primary consideration. Having a massively large and heavy pistol on your hip or shoulder holster is only comfortable for a while. When the going is tough, the pistol may well end up in your backpack. Just where the bear needs it to be when charging down on you.

Ideally, a pistol that’s as light as possible for ease of carrying around and one that has the longest barrel possible to ensure you get the most velocity and penetration out of the ammo you’re shooting.

My choice for bear protection is the Gen 4 Glock 21. The pistol weighs about the same as an all-steel .45 ACP with a single stack magazine holding six to eight rounds. The pistol has a barrel of 4.61  inches but, most importantly, is quick into action as you don’t have to fiddle with a safety catch before being able to fire.

The G21 has a magazine capacity of thirteen rounds plus one upfront. A high magazine capacity is vitally important when facing off against a bear. Statistics show that almost all bears put down by .45 ACP’s require multiple shots. 

Then again, I doubt if any of the bears were shot with modern hard cast 255-grain ammo, which is a real game-changer.  

Be Vigilant And Prepared

I feel it essential to bring the topic of mental preparedness into the conversation.

Bears are undoubtedly dangerous animals when you get into their personal space. They are large, noisy, and downright scary when you don’t have steel bars or a bulletproof sheet of glass between you and the bear.

Violent confrontations are not dealt with well by peace-loving individuals. Going from a situation of peace and tranquility while admiring the wonders of nature to a bear storming down on you is something that very few humans can mentally process.

Human instinct is to run when faced with danger. Unfortunately, most folks can’t help themselves and simply freeze in a panic situation as they are not mentally prepared for a dangerous situation.

Prepare yourself mentally by performing basic shooting drills wearing a kit similar to that you’ll wear outdoors. Going to see bears in zoos, watching bear programs on the telly, and mentally visualizing a bear charge while outdoors, and what you’ll do when this happens all help to take the edge off and build muscle memory.

Making yourself a bear-sized target to shoot at may draw a few strange looks at the shooting range, but it will stand you in good stead if you ever find yourself in a bear confrontation.

Most importantly, have your .45 ACP readily available when outdoors. Slipping the pistol into your backpack because your holster is uncomfortable can quickly kill you. No bear is going to wait for you to try and find your weapon in your pack before launching its charge.

Then lastly, be aware that a bear charge will not necessarily happen directly from in front of you. The odds are good that you’ll be striding along a trail minding your own business when all you hear is a grunt, groan, or growl coming from the side or from behind you.

Expect the unexpected, and you’ll have the upper hand. Should you hear anything suspicious, draw your .45 ACP. If a bear charges, aim for the center of mass and start shooting as soon as you are sure you’re in trouble and keep shooting. Fourteen .45 ACP rounds and a cool head will give you the upper hand.     


The .45 ACP caliber pistol is ballistically not the best choice of a handgun to use as a bear protection gun. To reach the vitals of an adult bear during a charge, the bullet needs to be able to penetrate well. Reliable penetration requires sufficient bullet velocity.

When using your trusty .45 ACP as a primary bear defense, the relatively low-performing carry ammunition needs to be replaced with +P 255 grain Hard Cast flat point ammunition to give you the best chance of stopping a determined bear attack.

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