Big-Bore AR Rifles for Survival

posted on September 26, 2016

In a survival situation, with guns, food, shelter or just about anything else, it’s always a good idea to have plenty of backup. For example, eating MREs will get old pretty fast and at some point you will be willing to lease your soul to the devil for a steak. Those who planned ahead will have the steaks.

The size difference between .223 Rem. (in the foreground), and .50 Beowulf, .450 Bushmaster and .458 Socom (in the background) is apparent.

Redundancy in your firearms ensures that you will have options, too. The AR-15-type rifle is the best firearm to survive a lingering crisis. While your primary battle rifles should be chambered for the most common cartridges to ensure ammo supply, a smart prepper does not stop there. Depending on where you live, you may be foraging for food. If that includes shooting big game or feral livestock, you should always bring enough gun.

Foraging with your AR-15 in a fighting cartridge might end in disappointment. I understand that .223 Rem. will kill deer or hogs, but not reliably, and on larger game it’s simply inadequate. If you are “sport” hunting and a wounded critter runs off, it’s tragic; but you are not in danger as a result. If you are trying to feed your starving family and the deer, elk, feral cow or whatever escapes after you wound it with an inadequate cartridge, it can be a very bad thing for all involved. The longer a crisis goes on, the tougher it’s going to be to find food by hunting, so every opportunity to shoot some protein will be important. Risking failure with a little cartridge is simply not smart.

The AR-15 design limits the length of the cartridge, so the only way to increase the power level is by going bigger diameter. That’s good, as heavy bullets at moderate velocity are well proven in the hunting fields.

Magazines for rifles chambered in .50 Beowulf are available in 4-, 7- and 10-round variants, corresponding to common 5.56 NATO magazine options.

Why not just use a powerful bolt-action hunting rifle? In a survival circumstance we must assume that the world will be a dangerous place. A magazine-fed, semi-automatic rifle in your hands gives you the best hope for winning a fight—whether it be against hunger, dangerous animals or two-legged predators.

Of course, bigger cartridges lower magazine capacity compared to 5.56 NATO, but the magazines will hold more ammo than a bolt-action and reloads will be much faster. For example, the .458 Socom uses unmodified, metal .223 Rem. magazines. The .223’s  30-round magazine holds 10 of the big boys. You also will have a lot of fight-stopping power with each of these bullets. I have never seen a complaint in the history books about the lack of stopping power from the .45-70 Gov’t used by the military in the 1800s. There are, on the other hand, a lot of complaints about the stopping power of our current 5.56 NATO cartridge and yes, despite what you read on the Internet, “stopping power” is a real thing. Don’t let anybody tell you that size doesn’t matter in a fight or when hunting. It does. Big bullets make bigger holes, smash more structure and rip up a lot more vital stuff than little bullets.

The current lineup of AR-15-based big-bore cartridges from mainstream gun makers is a short list of three.

(l.) When placing a .223 Rem. round and subsequent recovered bullet next to the .450 Bushmaster, it’s pretty clear which one makes a bigger hole. (r.) An AR-type rifle can be set up for close- to medium-range engagements, and the .450 Bushmaster is an excellent fight-stopper at these ranges.

.450 Bushmaster
The concept for the .450 Bushmaster was developed by the late Col. Jeff Cooper. He recognized that a big bullet is a good thing when shooting big game. He thought that the perfect rifle for most “general” big-game hunting would be a semi-automatic variant, larger than .44-caliber and capable of taking big game out to 250 yards. He called this the “Thumper” concept.

Tim LeGendre, of LeMag Firearms, developed the cartridge and named it the .45 Professional. He licensed the rights to Bushmaster Firearms International (BFI). Hornady worked in conjunction with Bushmaster and developed the ammo. The company modified the case a little so it would work better with Hornady’s proven SST Flextip bullet. With LeGendre’s permission, the name was then changed to .450 Bushmaster, and the cartridge was introduced in 2007.

Guns are available from Bushmaster and Remington. The current load from Hornady for .450 Bushmaster uses a 250-grain FTX bullet with a factory-advertised muzzle velocity of 2,200 fps from a 20-inch barrel for 2,680 ft.-lbs. of energy. Remington loads it with a 260-grain Premier AccuTip projectile at 2,180 fps. Muzzle energy is 2,744 ft.-lbs.

My favorite for all-around use is a handload that duplicates a planned Remington introduction that was canceled. It uses a 275-grain Barnes XPB Bullet designed for the .460 S&W, at 2,175 fps. I used it in Texas a while back where I shot eight hogs with nine shots. The finisher was because I hit one poorly and is no reflection on the cartridge. I also shot an Asian water buffalo that weighed more than three-quarters of a ton with that load.

Clearly, this cartridge will do for foraging or fighting, just as Cooper envisioned. The Colonel didn’t like the AR-15 because of the .223 Rem., but I’ll bet he would love this one.

When not in use for survival mode, the .450 Bushmaster is a fine choice for feral-hog-eradication purposes.

.458 Socom

After the fighting in Mogadishu in 1993, some of participants were disappointed in the performance of the 5.56 NATO cartridge and wanted something with a bit more knock-down power for the M16/M4-style rifles. The result was this cartridge. The .458 Socom was introduced in 2002, and while it didn’t gain widespread acceptance as a military round, it has found a home with civilians.

History has shown with the .45-70 Gov’t that a heavy .458 bullet at modest velocity is very effective, both on bad guys and big game. Military use mostly ended when the .30-40 Krag and smokeless powder replaced the .45-70 Gov’t in 1892, but hunters still love the cartridge today. I have shot several freezers’ full of deer, black bear, hogs and bison with the .45-70 Gov’t and can attest to its effectiveness. The .458 Socom was designed to duplicate the former military cartridge’s performance from an AR-15 platform.

(l.) The .458 Socom uses metal .223 Rem. magazines; the 30-round variant holds 10 .458 Socom rounds. (r.) Size matters. The .458 Socom has a big bullet that hits hard and makes a large hole.

The .458 Socom uses a lengthened .50 AE case with a rebated rim and is necked down for a .458-inch bullet. Unlike the straight-walled cartridges, which must headspace on the case mouth, the .458 Socom has a shoulder off which to headspace. This is a more positive approach to headspacing, enhancing accuracy. It also allows the bullets to be crimped in place with a roll crimp, which can be important with powerful cartridges to prevent bullet migration under recoil.

Rifles are from Rock River Arms, Wilson Combat, Southern Ballistic Research and perhaps a few more. Factory-loaded ammo is currently offered from three companies that I can find: Southern Ballistics Research, Wilson Combat and Cor-Bon, although I suspect there may be some smaller suppliers out there, as well.

One big advantage of .458 diameter is there is a wide selection of bullets on the market. Southern Ballistic Research offers 16 different loads for the .458 Socom, with bullet weights ranging from 140 to 500 grains. This cartridge probably is best suited to bullets in the 300- to 400-grain range. A 400-grain bullet at 1,600 fps duplicates one of my favorite hunting loads in the .45-70 Gov’t. That load was offered by Cor-Bon, but the company dropped it recently. It is, however, easy to handload with Speer Bullets.

One of the best bullets for any use short of the largest dangerous game is the 300-grain TTSX that Barnes developed specifically for this cartridge and it’s loaded by all three companies. Factory loads with this 300-grain bullet show it exiting the muzzle at 1,840 fps and with 2,240 ft.-lbs. of energy.

I have used two different Rock River carbines in .458 Socom, the CAR A-4 and the new X-1, and have been very impressed with the accuracy of both. Each shot right around 1 MOA with just about any ammo I tried.

One big advantage is that it does not require a cartridge-specific magazine and will run in standard metal .223 Rem. magazines. The .458 Socom is a powerful cartridge capable of taking anything in North America. It’s also designed by guys who have been to battle and wanted something better. This cartridge deserves a look from anybody serious about survival, hunting or defense.

(l.) The head of the .50 Beowulf case is rebated to the diameter of a 7.62x39 mm. (r.) Calipers are precise, but the .50 Beowulf bullet’s half-inch diameter could use a ruler.

.50 Beowulf
Bill Alexander, of Alexander Arms, was one of the pioneers of big-game hunting cartridges in the AR-15-style rifles. He developed this cartridge and named it after Beowulf, a legendary literary warrior who slayed the invincible Grendel by ripping his arm off. The day after that battle, Beowulf fought the monster that was Grendel’s mother and killed her by cutting off her head with a mighty sword from her own armory; a sword of which it was said, “no other man could have hefted in battle.” Years later, when he was an old man on the decline and but a shell of his former self, Beowulf fought and killed a dragon.

Clearly Beowulf didn’t need a “safe place” to hide from “micro-aggressions” like our modern “men.” He was a confident, competent, bad-ass dude and a great inspiration for this cartridge.

The .50 Beowulf was introduced in 2001 and was the first of the big-bore cartridges designed for the AR-15. The cartridge is based on a lengthened .50 AE case with a severely rebated rim so it fits a bolt head designed for the 7.62x39 mm cartridge. Bullets are .500-inch, the same as the .500 S&W Mag., so we have a good variety of options.

The Alexander Arms .50 Beowulf is capable of solid accuracy.

The .50 Beowulf bullet is half-inch in diameter and can expand to more than an inch. Compare that to a 55-grain .223 Rem. at .224-inch. The 400-grain Beowulf has 627 percent more bullet weight and an unexpanded diameter that is larger than a .223’s fully expanded bullet. Expanded, the Beowulf bullet has a 123-percent larger frontal diameter than the .223’s expanded bullet. The Beowulf has almost three times as much muzzle energy as the .223 Rem. and more than four and a half times the momentum. This is a serious step up in power for the AR-15 platform.

Guns and ammo are available from Alexander Arms and that’s where mine was spawned. Bullet weights range from 200 grains through 500 grains. The best match seems to be in the 300- to 400-grain range.

The 334-grain factory load from a 24-inch barrel has a muzzle velocity of 1,980 fps and 2,908 ft.-lbs. The 400 grain exits at 1,875 fps with 3,123 ft.-lbs. of energy. From my 16-inch gun, the 334-grain load is doing 1,900 fps, with 2,745 ft.-lbs. of muzzle energy. The 400-grain load is right at 1,800 fps and 2,878 ft.-lbs. of muzzle energy. So, clearly, this cartridge plays well with shorter barrels.

Some common cartridges for the AR-15-type rifle are, (left to right): .204 Ruger, .223 Rem., 6.5 Grendel, 6.8 SPC, 7.62x39 mm, .450 Bushmaster, .458 Socom and .50 Beowulf. As the projectiles get larger, so does their ability to quickly drop a threat.

I have used the Beowulf on numerous feral hogs and a few deer, always with very good results. With the right projectiles it hits hard, penetrates well and leaves a very large hole in its wake.

I remember the first time I shot my Beowulf; we were blasting at a piece of steel on a friend’s range. We had shot the steel with a lot of cartridges, with little or no real damage. But after two or three shots the Beowulf knocked it off its stand and when we went to hang it back up we were shocked to see the big bullets were making craters. Not the eroded-out holes that high-velocity bullet impacts make, but huge, deep indentations in the metal that left pigeon-egg-size bulges on the off side of the steel plate. Most steel-target damage is a result of high-velocity impacts or steel core bullets making holes or divots, but these were different. They were from the brute-force impact of these big bullets forging the steel into new shapes. That kind of raw power gets things done on any target.

Matching the terminal performance of the .45-70 Gov’t. in a semi-automatic, light carbine, the .50 Beowulf puts lots of power at your fingertips.

These cartridges are very specialized, but they do have a strong place in prepping, hunting or for defense. I would consider buying a rifle, or at least an upper that you can use with your current AR lower. Any of these three cartridges will make foraging much more successful and safer.

They also can be handy in some defensive situations. If you have a problem who’s hiding behind a barrier or something that needs breaking, like a bad guy’s car engine, these brutes can get it done better than any other AR-15 cartridge.

Besides, large-caliber rifles evoke the mighty .45-70 Gov’t and are just friggin’ cool. That’s gotta count for something, right?


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