Grizzly, Brown and Polar Bear Cartridges

By Chuck Hawks

.338 Win. Mag.
.338 Win. Mag. Illustration courtesy of Hornady Mfg. Co.

The great bears of North America are the largest land predators on earth. Grizzly and brown bears are actually the same species, the distinction between the two being geographic rather than genetic. The great bears of the Alaskan coastal region are called brown bears; inland they become grizzly bears.

The average female grizzly bear weighs about 400 pounds and the average male about 700 pounds. The famous salmon fed male brown bears of Alaska's Kodiak Island might run 1000 pounds and in extreme cases can weigh as much as 1600 pounds. Male polar bears average about 900 pounds live weight. Very large individuals can reach 1100 pounds, and in extreme cases males can weigh as much as 1550 pounds and females as much as 900 pounds. For all of these figures I am indebted to the research conducted and published by Edward A Matunas in the 47th Edition of the Lyman Reloading Handbook.

When you realize that the average male Jaguar of South America weighs about 200 pounds, the average adult male African lion weighs about 330 pounds and an adult Bengal tiger might weigh 450 pounds, the massive size of the great North American predators is brought into chilling perspective. In the days before the white man decimated the bison of the North American plains, grizzly bears regularly preyed upon these massive bovines!

While .30-30 and 6.5x55 caliber rifles have felled large numbers of these monsters, such feats were usually performed by explorers, residents of the far north and indigenous substance hunters. 12 gauge shotguns stuffed with slugs or heavy buckshot have been carried for protection against large bears and the great cats, with mixed results. The Maasi tribesmen of Africa traditionally killed lions with a spear. Unfortunately, while all of these weapons are better than nothing, a powerful rifle is far superior. Modern sportsmen are best served by something other than a spear, a shotgun, a .30-30, or a 6.5x55 when hunting the great predators of Africa, North America and the Arctic.

The great bears have thick fur, tough skin, heavy bones and very strong muscles. Premium, controlled expansion bullets are the medicine of choice. The Nosler Partition bullet, for example, has been a favorite of experienced Alaskan hunters for decades.

The minimum recommended calibers for all of the great bears are the .30-06 Springfield with 180 grain (SD .271) to 220 grain (SD .331) bullets and any of the standard length 7mm Magnum cartridges with 175 grain (SD .310) bullets. In addition to the .30-06, other suitable standard cartridges include the .338-06 A-Square and .35 Whelen, both with 225 to 250 grain bullets.

The most recommended calibers are the standard length and long .300 Magnums with 180 to 220 grain bullets, 8mm Magnums with 200 grain (SD .274) to 220 grain (SD .301) bullets, .338 Magnums with 225 grain (SD .281) to 250 grain (SD .313) bullets, .35 caliber Magnums with 250 grain (SD .279) bullets and .375 Magnums with 270 grain (SD .274) to 300 grain (SD .305) bullets.

Seldom encountered in North America, but perfectly suitable, are the powerful European 9.3mm (.366") calibers. These include the 9.3x62, 9.3x64 and 9.3x74R with 270 grain (SD .288) or heavier bullets. In the same general class is the much newer .376 Steyr with 270 to 300 grain bullets.

The .30-06 and the 7mm Magnums offer muzzle energy (ME) in the vicinity of 3000 ft. lbs. and up. The highly recommended .300 Magnum and medium bore calibers offer ME figures from about 3400 ft. lbs. to about 4400 ft. lbs.

Any rifle more powerful than a .375 H&H Magnum (ME 4200-4400 ft. lbs.) is getting into the overkill area, even for the great bears. No hunter pursuing dangerous game should saddle him or her self with a rifle so much more powerful than required that it induces flinching, reduces the chances of accurate bullet placement, or is so heavy that it is slow to swing. As always, bullet placement is the key to killing power. A 180 grain bullet from a .30-06 in a vital spot will drop the biggest Kodiak brown bear in Alaska, while a bullet from a .458 Magnum in the guts is an invitation to disaster. Every hunter owes it to himself, the game animal and innocent bystanders to use a rifle in a caliber that he can consistently shoot accurately.

That said, for those who can control their massive recoil, big bore rifles from .40 to .45 caliber using bullets with sectional densities similar to those mentioned above can be used to deadly effect on the great bears. These would include such diverse calibers as the .450/400 NE, .400 H&H Magnum, .404 Jeffery, the various .416 Magnums, .450 Marlin, .450 NE and .458 Winchester Magnum.

In a survey taken a few years ago, it was found that the most popular caliber with Alaskan professional hunters and guides responsible for "backing-up" their clients was the .338 Winchester Magnum. With typical factory loads using 225 to 250 grain premium bullets the .338 Win. Mag. has a ME of about 3860-4046 ft. lbs. and a maximum point blank range (+/- 3") of about 270 yards. These can be taken as ideal ballistics for hunting any of the great bears. Recoil energy runs about 34 ft. lbs. in an 8.5 pound rifle.

While grizzly, brown and polar bears have been killed at very short range and very long range, the preferred range is between 50 and 150 yards (or meters, if you prefer). This is close enough to allow accurate bullet placement and far enough to allow time for follow-up shots if required.

In closing I can only reiterate that while a rifle of adequate power is important when hunting any of the great bears, accurate bullet placement is absolutely paramount. Predators so massive and deadly should never be taken lightly. Hunters must be completely confident of their ability to put the first bullet where it will do the most good!

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Copyright 2006, 2016 by Chuck Hawks. All rights reserved.