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Loaded for Bear: Is 10mm Sufficient?

Spring fishing season is upon us.  Cold streams tumble out of the rockies not yet filled with sediments of major snowmelt and summer is mere weeks away.  With summer comes backpacking into the wilderness, camping trips, followed by archery season and the general rifle big game season.  Why state the obvious?  All of these recreational endeavors tend to take humans into bear country, especially in the Norther Rockies of Idaho, Wyoming and Montana.  It is a given of course if you are reading this from Alaska.
As a 22 year resident of Montana, and having lived on the borders of both major national parks (YNP & GNP), I have had the opportunity to, hike, hunt, fish, camp and explore in the wilderness and national parks of Grizzly country for over two decades.  As a teenager I had the privilege to work for an outfitter near the Yellowstone Park border in the Absaroka Beartooth Wilderness.  In those years and still currently, I have backpacked, hiked and hunted thousands of miles of vast country that is home to Grizzly bears.  I have met bear attack survivors, known personally individuals who were forced to kill a bear while under attack, and have had near bear encounters myself.
Now, none of this makes me an “expert” on bear encounters, quite the contrary – however, it does provide me an edge over the many internet forum experts who espouse the merits of certain calibers for their “bear load”.  Even the supposed real “experts” in Canada recently amended statements regarding the theory of “playing dead” and revised it stating we should now fight back , as well as this statement from Bear Encounters In the Backcountry:
“If the bear attacks, use your deterrent and fight for your life. Kick, punch or hit the bear with whatever weapon is available. Concentrate your attack on the face, eyes and nose. Fight any bear that attacks you in your building or tent.“

As an avid outdoors enthusiast, I carry both bear spray and a firearm.  I do not view these great bears as an enemy, a competitor or an evil creature that seeks to destroy us.  Indeed, I love the bear.  Striving to avoid bear, being as they say, “bear aware”, making noise and observing ones surroundings can many times alleviate any confrontation from occurring.  I hope to not have to take a bear in self defense, just as I hope to not have to take any human life in order to save mine.  However, in order to protect myself or others, I am willing to dispatch of a bear if thrust into the situation.

This article is not about bear spray.  Yes, as stated I carry bear spray.  I can also recount confirmed instances where pepper spray did not work, one case in particular where 2 cans were sprayed on one bear and a female hiker was still mauled to death with her companion bearing witness.  High winds are ever present in the rockies and can quickly reduce the efficacy of a bear spray plume.  Each encounter and bear is unique, the circumstances, and behavior of all parties involved will ultimately dictate the direction the encounter takes.

Skokie Illinois Grizzly Pop: 0

As stated above I am not an expert on the subject however, based on my observations and experiences listed above, I feel I can offer an opinion on the firearm calibers of choice one should consider when arming to protect against a bear encounter.  The internet seems to be rife with this debate topic.  Forums are filled with suburban weekenders, and inner city preppers who tend to dwell on the topic of “loaded for bear”, with various theories on which firearm or caliber one should choose.  Many of these opinions are born in minds that rarely have set foot, and may never have – in Grizzly habitat.  Often you see opines of this subject from individuals whom hail from the wilds of Skokie Illinois, Pittsburgh, and Miami.  It becomes difficult to take your input on this subject serious.

Before we get right to calibers and firearms, let’s first address the animal.  The Grizzly is a majestic and large omnivorous mammal that inhabits the Rocky Mountains.  There is now discussion about removing them from the endangered species list, as their numbers have successfully rebounded in key regions of the Rockies.

In recent times these bears are seen returning to the Great Plains, where they forage in creek bottoms and river banks.   It is here that Pheasant hunters in Montana have had several encounters and even attacks in recent years.

Grizzly on carcass in Yellowstone

The largest Grizzly documented in Montana died in 2007 and weighed 830 pounds .  This is above average, with males weighing in at 600 lbs. and females, 300-400 lbs.  They come out of hibernation typically at the end of March – mid April depending on the weather, where they drop into the valleys and begin to drearily search for food and restore the winters lost fat stores.  Summer sees the great bear rearing cubs, feeding on berries, roots, pine nuts and high alpine moths, as well as the occasional carcass.

These large bears can be very territorial over their food supplies, protective of their cubs and become aggressive when surprised.  Grizzly can sprint 35 mph – far faster than the fastest human.  Their long claws and easily tear human flesh and their jaws, deliver bone crushing bites to the skull, neck or appendage of any man.
Pull up a chair, sit on my lap, it’s story time.  I told you that I knew several attack victims, and let me briefly recount some of these attacks for you here.
Just north of Yellowstone, I used to hunt antler sheds near Red Mountain.  One of the individuals I would scour those dark woods and blonde hillsides with was the son of a rancher/outfitter who was attacked in the very woods we would collect the bone treasures of elk.  I remember the tree specifically.  As we descended the side of the mountain one day, he pointed out a stand of timber to our right, not far off at all.  He pointed to the tree.  His father, whom I knew had been attacked there – “Right there is where he was attacked” he stated, “Doctor said it was his leather vest that saved his life.”  His father had jumped a Grizzly sow and cubs.  Before he could muster a thought the bear immediately charged, surprised by his presence and knocked him to the ground.  She placed her claws onto his back, dug into his thick elk hide vest he had fashioned for himself and dragged her paws down towards his belt.  During the chaos – I cannot even imagine, she flipped him over, spun him and then ran off several yards.  Dazed, the man sat up and saw her looking back at him.  Her eyes locked onto him and she turned – sprinting at full speed back towards him, grunting and huffing, tearing the forrest duff beneath her stride, closing the distance.  He was laying beneath a Lodgepole Pine and decided to put the tree between himself and the sprinting Grizzly.   He rolled/scooted behind the tree, and that action was quickly followed by a resounding, “THUD!” – as the bear impacted the opposite side of the tree with her head and chest.  The bear fell over, stood up, staggered, appearing dazed, and sprinted away, gathered her cubs she was off.  With some cracked ribs, and various other non-life threatening injuries, my friends father was able to make it down the mountain alone and alive.  I had seen the vest that bore the deep gouges of the grizzlies claws that would have surely harvested his lungs through his back, had he not wore it that day.

This next story made national news.  Near the borders of the Bob Marshall Wilderness, a friend was returning to a kill site to harvest meat after a successful hunt, when he and another individual surprised a Grizzly sow and two cubs on the kill.  She charged, knocked down the other individual and tore into his legs.  As he lay their screaming, “Shoot her!  SHOOT HER!”, my friend had to work the bolt on the one hunting rifle they brought back to the kill site and fire 3 rounds at near point blank range, finally killing the bear.

There are numerous other accounts that I am not as close to, which have occurred and made the news over the years here in Montana.  Each unique in ways, while others have recurring themes, as you saw above with cubs and a sow, others involving a food source or a surprised bear.  There have even been instances where the mere report of the firearm discharging was enough to frighten the bear away from those being charged.  Nearly each year there are encounters, maulings and even deaths in the National Parks, as well as surrounding wilderness, where literally millions of humans converge to recreate during the months when the bears are the most active.  There will surely be encounters this year as well, as humans increasingly enter the wild.

We have all perhaps heard the adage, “Before you take that handgun for bear, be sure and file that front sight off smooth.” If an individual has not heard this humorous quip they tend to innocently ask, “Why?” Which is then followed by a gruff, “So when the bear shoves it up your ass it don’t hurt so bad!”  I first heard this from the outfitter I worked for as a youth.  He would in fact often carry a sidearm, however his primary, go to recommended bear gun was a 12 ga. with slugs and “00” Buck.

Mossberg 500 Persuader

Having carried a shotgun for bear on a couple of trips, I can tell you that they are cumbersome, larger than ideal, and often, one does not parade about camp, venture to the latrine, or walk about the fly fishing stream with the shotgun slung – for obvious reasons.  Often, I found that we carried it into the wilderness, where it idly sat leaned upon a tree or in a tent the remainder of the outing.  A pistol was always more suited, being fixed upon my hip throughout my trips.  My first bear handgun (regrettably sold) was a Colt Anaconda 44 mag.

1502 fps / 3014 ft. lbs

The energy of the 12 ga. slug is ideal. Reaching over 3000 ft. lbs. of wallop it’s easy to see why so many guides recommend it.  This brings up a main point of this article that we will hopefully purvey to the viewers:  ENERGY.  The outfitters, the guides, the men who live and breath in the wilderness of the Grizzly, always come back to two words: Foot Pounds, in other words ENERGY.  You must quickly, deliver, enough energy to stop a very large, strong animal. These same individuals often recount the lack of time one has in order to deliver that energy.  I remember one stating, “Seconds, you have only a few seconds and one maybe 2 shots to get off if you are lucky.”

So we have little time, and we need to deliver enough energy to penetrated and crush what I will also recount from these knowledgeable individuals, “The round needs to be able to penetrate and crush through 3 feet of hide, fat, muscle and bone.”  

Smith and Wesson 629 44 Magnum

It is here that we get into the controversy of firearm / caliber choice.  Based on my life experience in this habitat, frequency of my time spent a year venturing into these wilds, knowledge of encounters and first hand accounts, it is my opinion that the minimum qualifying cartridge for this type of encounter is the 44 magnum, firing a max SAAMI spec load featuring a hard cast, flat nose bullet of high grain weight.  The 44 Magnum can be loaded within SAAMI spec to reach nearly 1100 and even 1200 ft. lbs of energy.  I personally carry the “Bear Load” from HSM seen below.  That load is in the 1075+ range depending on your barrel length.  Others who carry more robust 44 magnum revolvers elect to carry the hot +P and +P+ loads of Buffalo Bore – reaching energy levels of 1649 ft. lbs.

340 Grains 1649 ft. lbs
305 Grains 1075 ft. lbs
460 Smith and Wesson

I hunt with a gentlemen, whose pistol has been on the channel before – a 460 Smith and Wesson.  It is a powerful revolver that delivers an incredible 2,860+ ft. pounds of energy.  This is very close to and even matches some 12 ga. slug loads.  The pistol is quite heavy with weight being 60-70+ ounces depending on barrel length however he has carried this pistol for several years, over mountain ridges and trudging through dense brush in the wilderness.  The pistols mere presence on another capable mans hip brings a peace of mind when in the neighborhood of the great bear.

360 grain 460 = 2,860 ft. lbs.

Whether it is a 44 magnum, with the minimal energy of 1070-1600 ft. lbs, the 454 Casull ranging from 1500-1700+ ft. lbs, the 460 Smith and Wesson at 2,860+ or the 500 Smith and Wesson ranging from 1700-2500 ft. lbs, it is my opinion that these pistol calibers no matter how uncomfortable to shoot, offer the minimum energy in which to fire 1 maybe two rounds into an aggressive, attacking grizzly.

220 grain 10mm 703 ft. lbs

In choosing these above calibers, having longer case length to accommodate more powder and thus subsequent higher pressures and velocities, we are then confined to the revolver pistol platform.

There is a cadre of my friends and acquaintances who chose to purchase the semi-auto platform Glock 20 in 10 mm for the following reasons: weight, semi auto (less recoil), rapid follow up shots (more bullets into bear), more ammunition capacity.

Glock 20 (10mm)

Addressing the ENERGY aka ft. lbs.- the 10mm  cartridge delivers energy in the ranges of 500-750 ft. lbs.   This is a far cry from the energy delivered by the above mentioned calibers.  In the opinions of many an outfitter, guide and those far more experienced and knowledgeable on the matter than I, this is not sufficient to STOP an aggressive bear.  Many who carry the 10mm may not even realize that the load they have chambered (unless being a “hotter” load) is likely delivering a mere 500 ft. lbs of energy.

Often I hear phrases like, “shoot ability”, “recoil”, “fast follow up shots” as a defense for choosing the weaker 10mm. Uh-oh!  I said weaker.  Yes, it is weaker.  This is usually when some dear friends who pack the ten start to recount how they will riddle that bear with a barrage of lead – perform a speed reload, ramming and jamming a second mag and riddling him some more, as if the 10mm lead shower will cleanse the ursus arctos horribilis’ thoughts of absolutely disemboweling them.  (humor added)

Time – you don’t have it.  Remember, this is happening faster than the speed of thought.  This bear is closing 40 yards to zero in just over 2 seconds.  This situation will require subconscious, high stress weapon manipulations on demand with the resulting 1 or 2 shots you do manage to squeeze off dictating your survival.  Needless to say, practice makes perfect, and just as with any high stress shooting event, drilling, shooting and time on gun is critical to ensure the desired outcome.

High magazine capacity and fast follow up shots will not dictate the outcome of this event.  This is not a gunfight with some 107 pound tweaker wielding a 25 auto. Additional hits with a weaker cartridge will not make up for the lack of penetration, absent insult, and non-disruption of vital organs, unless you somehow manage to eek out a miracle T-zone shot on a charging bear.  In that case – bring a .22 magnum.

The cartridge – one, two maybe generous third you are capable of getting downrange, need to (must reiterate), penetrate and crush up to 3 feet of hide, fat, muscle, bone and organs.  This is the largest predator on the continent.  10mm is an anti-personnel, military/LE round designed to neutralize bi-pedal higher mammals weighing 110-200 pounds aka it’s an anti-monkey round.  You are being charged by an upwards of 800 pound, tenacious beast that has a pain tolerance unimaginable to any human.

Bear Taken with 44 Magnum

The point of the above diatribe is this; you may have 15 rounds of sub-par 10mm loaded in a cute Glock 20 (I own 4 Glocks so this is not an anti Glock piece)  however you will be lucky to get off 3.  Even if all 3 were hits, where did they hit?  Did they indeed penetrate, disrupt and destroy the necessary connective tissues, bones and organs to STOP the threat?   I don’t care if a Glock 20 has 500 rounds.  By this logic train, we can make up for the Glock 20 with a .22 that can fire 1000 rounds a minute and slowly chew the bear to pieces.  Death by a thousand needle pricks does not work here.

The venerable accuracy and reliability of the revolver platform spans well over a century.  For nearly 100 years, it was the sidearm.  In my opinion of firearms, this is perhaps one of the last vestiges where the revolver holds its own and remains unchallenged in its ability to dominate the field of ballistics required to address large threatening mammals.

AK Hunter Attacked On Moose Kill – Bear Taken With 44 mag

I would urge readers to truly consider the facts, evidence, and experiences of others prior to staking their safety on the 10mm in Grizzly habitat.  Now if you live in Maryland, New York, Virginia or New Jersey – areas with perhaps some black bears go ahead and get the 10mm.  If you live some place with cougars or perhaps just a people problem – get the 10mm.  However, if you spend significant time in Grizzly country, look into revolvers, shoot a few, and evaluate it from a different angle.

Take a moment to watch Mr. Jerry Miculek below, send 6 shots of 44 mag in one second.  As well as the video with a large Alaskan Bear dropped by a 500 Smith and Wesson.

Thank you for your time and consideration.  Be safe out there as you wonder those wind swept ridge tops of squeaking lodge pole.

INCREDIBLE RESOURCE OF LINKS:

Efficacy Of Firearms For Bear Deterrence In Alaska

Safety In Bear Country: Protective Measures and Bullet Performance At Short Range

Brown Bears Killed In Defense of Life or Property On the Kenai Penninsula

*Addendum:  One thing we did not discuss as it relates to the 10mm Glocks, is the subject of what some term, “unsupported chambers”.    Most pistols, especially revolvers have fully supported chambers, meaning the chamber that houses the live cartridge fully encircles the case nearly to the back rim of the cartridge.  This becomes most critical in high pressure, +P loads where chamber pressures can stress the cartridge and any “unsupported” are of that case to fail.  This case rupture and failure can lead to injury, damage to the firearm, and the inability of that firearm to further function.  Pay attention to this subject and do some independent research – if you happen to carry a Glock 10mm.

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About the Author

Denny Ducet I addition to writing for The Arms Guide, Denny operates his own blog, and youtube video channel where topics include firearms discussions, reviews, and training ideas. Having over 13 years of time on the job and in continuous training Denny brings tactical medicine to The Arms Guide. A.A.S. NREMT-P, P.O.S.T. SRT/SWAT Medic 2006-Present, TCCC, PHTLS, PALS, PEPP, AMLS

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