The Best Handgun Cartridge (and Ammo) for Grizzly Bear Defense

We hope you enjoyed that AI generated grizzly bear encounter, but if you run into a grizzly bear it’s no laughing matter. If you spend any amount of time in grizz country, you know that wavering your arms, trying to look big, or shouting isn’t going to deter an angry grizzly bear from eating you (all of the classic bear “defense” techniques). So, what firearm should you own for grizzly bear defense? What cartridge should you be shooting? And, what ammo? We answer all of those questions so you don’t end up as bear bait.

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Understanding Grizzly Bears

First off, we need to understand grizzly bears to determine all of those aforementioned answers. Can you outrun a grizzly bear? Absolutely not. We covered this in lengthy detail earlier this year. Not only is the temperament of a grizzly bear the nastiest of most all of the bear species, but they also can haul you know what by clocking sustained speeds of 40 MPH. So, coaxing a grizzly bear to leave or running away is not an option. If a grizzly bear has chosen to attack, it is time to stand your ground and defend yourself.

The Medicine – What Cartridge Should You Deploy?

You need a terminal hit on the grizzly bear; meaning, you impactfully strike the brain or central nervous system shutting down the animal in its tracks. This is not a sporting double-lung/heart shot scenario. It is estimated that bears have 30 – 60 seconds of oxygen in their blood if you shot one through the heart in self-defense. This gives them – and sadly, you – an eternity where the grizzly bear could still maul and kill you. Therefore, we need a stout cartridge that can crush bone, muscle, and tissue to achieve that desired terminal hit.

Semi-Auto Cartridge: 10mm Auto

Often plainly called 10mm, the full name is 10mm Automatic Colt Pistol – also known as 10mm ACP or 10mm Auto – paying homage to Colt who was one of the first manufacturers to mass produce a firearm chambered in 10mm (the Colt Delta Elite). The 10mm cartridge has the energy we desire to achieve that terminal hit. You can find ammunition in excess of 600 Foot-Lbs of energy or higher which is what we want. Here are some suggested firearms if 10mm is your cartridge of choice:

Revolver Cartridge: 44 Magnum

The 44 Magnum round, also known as .44 Remington Magnum, was made prominently famous for being called “the most powerful handgun [cartridge] in the world” by Clint Eastwood in Dirty Harry. That moniker isn’t just legend in cinema. The 44 Magnum is a legendary cartridge in hunting circles as well. It is considered the “starting point” when it comes to revolver grizzly bear defense. Anything less isn’t stout enough to get the job done, and anything larger has failings (difficult-to-source ammo, expensive ammo, few firearm options, poor holster options, etc). Here are some suggested firearms if 44 Magnum is your cartridge of choice:

Which Ammo Packs the Most Punch? Grizzly Bear Defense

When selecting the ammo for our 2 chosen cartridges, we need to be equally picky because under a high-stress, harrowing situation like defending yourself from a grizzly bear, you may not make a perfectly, well-placed shot. So, if you have Foot-Lbs of energy on your side, hopefully that can stop a charging, violent bear.

Best 10mm: Underwood Hard Cast 220 Grain Flat Nose (704 Ft-Lbs)

The best ammunition you can be packin’ for grizzly bear defense – by an overwhelming margin – is the Underwood Hard Cast 220 Grain Flat Nose rounds. This 10mm ammo packs a stifling 704 Foot-Lbs of energy at the muzzle, and its hard cast bullet design is perfect for crushing the bone, muscle, and tissue of a raging grizzly bear. At $27.99 per box of 20 rounds, it is not ridiculously priced and it is absolutely what you should be carrying if 10mm is your cartridge of choice for grizzly bear defense.

No plastic burning smell
Thermally stable
Resistant to weathering and chemical degradation
Strong mechanical and tensile strength properties
Self-lubricating
Able to withstand high pressure conditions
Able to withstand high heat conditions
High degree of wear and abrasion resistance
Reduced friction resistance
Good flame retarding properties
Coating prevents lead to bore contact thus virtually eliminating lead fouling
Shoot higher velocities without lead fouling

Honorable Mention: Buffalo Bore “Heavy” 180 Grain Jacketed Hollow-Point (728 Ft-Lbs)

A second place finish for the best grizzly bear defense ammo you can be toting if 10mm is your chosen cartridge is the Buffalo Bore “Heavy” 180 Grain Jacketed Hollow-Point (JHP). These are a bit spendier at $41.97 for a box of 20 rounds, but can you really put a price tag on your safety?… This round appears to be better on paper with its 728 Ft-Lbs of energy, but being as it is a hollow-point, it may stop when confronted with bone as opposed to crushing its way through. Perfect for nearly any other critter you need defending from, but hard cast is king when it comes to achieving a terminal hit.

Best 44 Magnum: Buffalo Bore “Dangerous Game Heavy” 265 Grain Mono-Metal (1,195 Ft-Lbs)

These heavy-hitters are delivering rifle power in a handgun so be sure to grip your revolver tight. This is for when you need SHTF self-defense against one of North America’s most apex predators imaginable. The mono-metal bullet ensures a little bit of bone or surly temperament from a grizzly bear isn’t going to deter this bullet from its path. It kicks like hell and hits even harder. Exactly what you need during the butt-puckering moments of defending yourself against a grizzly bear. The Buffalo Bore “Dangerous Game Heavy” 265 Grain Mono-Metal sells for $67.57 per box of 20 rounds and would be well worth it.

Honorable Mention: Black Hills 240 Grain Jacketed Hollow-Point (846 Ft-Lbs)

The Black Hills 240 Grain Jacketed Hollow-Point (JHP) is a venerable offering that won’t rip your revolver out of your hand, but hopefully it still stops a grizzly bear dead in its tracks. Black Hills Ammunition is known for being extremely high quality as they have ammo fielded with all 5 branches of the US military. This ammo should serve you equally well if you need to drop a fuzzy semi-truck you encounter in the woods.

Departing Thoughts

Bears are a fascinating and beautiful animal that deserve our respect. Especially brown bears (grizzly, kodiak, etc) as their temperament is on another level where they will rip your face off just for breathing. Your best defense is situational awareness, seeing them before they see you, and avoiding them entirely. If you must defend yourself with a firearm, “bear” in mind that 10mm and 44 Magnum are your best options depending on if you lean closer to revolvers or semi-autos. Then, choose quality ammo as well. If you take caution out in the woods and follow this guidance, you’ll be alright. As always, let us know all of your thoughts in the Comments below! We always appreciate your feedback.

Adam Scepaniak