The constraints start with selecting an autoloader that a girl can use to defend against a large bear. I add that it could be said this bear is charging her. My argument is partially based on a quote from Dick Metcalf who is the author of "Handgunning For Bears" which was published in Petersen's Hunting Magazine. Since he says ANY BLACK BEAR, he limits it to 500 to even 800 Lbs bears. The largest Black Bear on record was over 800 Lbs. Now some people on the thread say that penetration is very important when stopping large powerful game and that solids are needed. I say that based on the dimensions of a large bears head that penetration needs to be at least 10.5 inches of thick hide, jaw muscle and skull bone and that stopping power is needed. You can tell I'm visualizing a head shot. I think a head shot to the cranio-ocular cavity is a best case scenario. Factors like accuracy and reliability of the firearm are considered. That being said, the constraints are satisfied by the following selection.

The Glock 20 in 10mm Auto; hand loads of 180 grain Gold Dot Hollow Point charged with 10.5 grains of Blue Dot powder, using CCI large pistol primers, and new Federal brass case. The user having three 15 round magazines all bundled up in a Desantis shoulder holster; this being most practical for Alaska type environment.


Why the Glock 20? 1. Functional Reliability, 2. Ease of Use, 3. Stopping Power, 4. Fire Power, 5. Versatility, 6. Availability, 7. Availability of Night Sights 8. Cost.

Why the 10mm? The 10mm Auto will push a 200 grain slug at a max velocity of about 1,100 feet per second producing 537 foot pounds of energy at the muzzle. The sectional density is .161 and I'm not sure if this is considered big bore but it's not little. I do know that the 10mm Auto takes large pistol primers. Keep in mind this information is based on safer data, there are some loads that actually outperform the preceeding in terms of muzzle energy but I don't feel that they are as safe. This Following link is a load pushing a 200 grain slug traveling at 1300 feet per second and producing 750 foot pounds at the muzzle! These guys really push it. I would not select this ammo because I prefer jacketed and don't feel it's important to abuse my firearms that much. Plus the lead fouling would be terrible to try and clean out.

Why Gold Dot; Bonded Bullets? It may not be a "solid"; its better, having controlled expansion resulting in deeper penetration than other hollowpoints but having better stopping power than a solid. GD Bonded HP's out perform all other Hollow Point and Solid bullets in the .40cal, especially when used in 10mm Auto full power loads for bear defense; handloading is necessary because there does not seem to be a 10mm Auto Full Power load for 180 Grain GDHP on the market probably due to the .40 S&W craze, none the less, the GDHP Bonded is the first HP bullet to retain it's mass at 95% on average, some studies show 100% mass retention in 10% ballistic gellatin, the best retention of mass of any bullet since 1965 meaning it will penetrate well and have controlled expansion regardless. This is because the bonded jacket-core bond is stronger than the bond lead has to itself. Since the bullet needs to penetrate and cause a large temporary wound cavity with a large permanent wound channel the bullet has to have (controlled mushroom or expansion). Since 10.5 inches of thick skull bone, hide and muscle is the minimum depth any bullet would need to travel the 180 grain GDHP will actually work because when handloaded it can safely reach the max velocity of about 1250 feet per second and producing 624 ft-lbs of energy at the muzzle if using 10.5 grains of blue dot (the max powder charge) and since it's a GDHP bullet the expansion is delayed for best penetration. Note: the sectional density of a .40 cal bullet that weights 180 grains is .161; if anyone cares.

Why Blue Dot. This powder is the best for this purpose based on performance and availability.
Why carry three magazines? For if you drop your piece in a river. (speaking from experience) It's nice to know you have two other dry mags.

Psychological factors.

No firearm will make you feel better about being charged by a bear. Note: If a .45 Auto and .40S&W can kill a bear so can a 10mm Auto by definition.
CONCLUSION: The best way to get the 10mm Auto to work for large bear defense is to use a Glock Model 20 with 15+1 capacity and fill the magazine with hand loads of the 180grain GDHP carrying a charge of 10.5 grains of Blue Dot powder in a new federal 10mm Auto case using a CCI large pistol primer that is quality checked by an experience hand loader. GETSOME!


I should note, handloading requires skill, if you decide to handload make sure you have an experienced hand loader show you the ropes first and make sure you follow the book.