Skip to content

AR-15 Rifles

Modern sporting rifle

What is an AR-15?

The AR-15 is a lightweight, rapid-fire, semi-automatic rifle with a long history in military applications, and a growing market among the civilian population as a home-defense, sporting, and all-around consumer rifle. The AR-15 was originally introduced in 5.56 mm but is now available in a wide variety of calibers, with nearly as many add-on features. This customization and versatility has made it a very popular rifle, and it even has its own designation as a “Modern Sporting Rifle.”

The AR-15 was originally introduced in 5.56 mm but is now available in a wide variety of calibers, with nearly as many add-on features, making it a very popular rifle, so popular, that it has its own designation as a “Modern Sporting Rifle”

A Brief History of the AR-15

The story of the AR-15 is like doing your homework in the back seat of a school bus bouncing down a rough gravel road, in other words, there were some bumps along the way. The original AR-15 came from the earlier ArmaLite AR-10 designed by Eugene Stoner. Colt purchased the rights to the AR-15 in 1959 and held exclusive control until patents expired in 1977, leading to widespread manufacturing by other companies. An assault rifle ban from 1994 to 2004 halted production of most models in the United States, but since then, the supply has grown to match the demand and the AR-15 is the most popular rifle platform in America.

AR-15 Calibers

The variety of cartridges chambered by the AR-15 is a great indicator of the popularity of this rifle platform. From small rimfire to heavy caliber center-fire ammunition, there is a caliber for nearly everyone in an AR-15.

5.56 mm NATO

The original caliber, and still the best in the opinion of many shooters. The 5.56 NATO cartridge for the AR15 platform is effective to long range, has few malfunctions, and doesn’t jam very often. The original military version of the AR-15 was the M-16, and it had a reputation as an unreliable, jam-prone rifle in early combat in Vietnam. Those issues were corrected with a few small design changes in the early 1960s. Today, the 5.56 is a popular version of this gun thanks to its rapid rate of fire, minimal recoil, and high accuracy.

5.56 NATO Performance

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 3,060 1.289 N/A
100 2,714 1,014 +2
200 2,394 789 0
300 2,095 604 8.6
400 1,820 456 25.6

.223 Wylde

Many claim the 5.56 NATO and the .223 are interchangeable cartridges. Though each will chamber in rifles designed for the other cartridge, they are not safe to use interchangeably. The pressure in the 5.56 is slightly higher than the .223 at 58,000 vs. 55,000 pounds and when fired in a rifle not designed for the 5.56 it can dangerously increase the ignition pressure, driving primers backward, damaging the gun, or injuring the shooter. The reverse also causes damage since there isn’t enough pressure to properly cycle the weapon. The ballistics between the two rounds fired properly is similar with the .223 slightly faster with a smaller bullet, but the 5.56 with a larger bullet has more energy. The .223 Wylde is a popular caliber for use with the AR15 platform.

.223 Remington Performance 62 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 3,250 1,242 N/A
100 2,849 953 +1.6
200 2,482 722 0
300 2,203 539 7.5
400 1,883 393 22.7

.224 Valkyrie

A relative newcomer to the AR-15 world, the .224 Valkyrie is a cartridge designed specifically for the AR platform. With a 60-grain bullet, this is a fast, powerful caliber that delivers a tremendous amount of energy for its size. Many claim the .224 Valkyrie is comparable to the 6.5 Creedmoor in performance as a long-range varmint rifle, and the case design allows quick, reliable cycling with the AR-15 semi-automatic mechanism.

.224 Valkyrie Performance 60 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 3,000 1,451 N/A
100 2,763 1,139 +1.3
200 2,539 885 0
300 2,325 679 6.6
400 2,122 512 20

.22 Long Rifle

The .22 is without a doubt, the most often fired cartridge in the United States. Almost everyone began their shooting and hunting career with a box of rimfire .22 Long Rifle cartridges. The .22 LR in an AR-15 platform can provide a lot of inexpensive fun while teaching youngsters the art of shooting and engaging more experienced shooters with the joy of plinking or taking small game. You can shoot a long time for just a few bucks with an AR chambered for .22 rimfire ammunition.

.22 Long Rifle Performance 30 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 2,200 269 N/A
100 1,383 106 0
200 974 53 17.5
300 N/A N/A N/A
400 N/A N/A N/A

.300 AAC Blackout

More energy at shorter range is the draw of the .300 AAC Blackout as an AR-15 cartridge. This alternative to the NATO 5.56 mm has a faster muzzle velocity and maintains that speed over 300 yards, but the bullet drop is so substantial beyond the 300-yard range that it is ineffective at longer distances.

The energy and accuracy of the Blackout make it a popular choice for a home defense weapon, and it is equally popular with military and police around the world. If you’re a varmint hunter, it’s not a great option.

.300 AAC Blackout Performance 110 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 2,750 1,763 N/A
100 2,580 1,552 +2
200 2,417 1,362 0
300 2,260 1,190 7.8
400 2,108 1,036 22.2

6mm ARC

Long-range shooting, that’s the simplest answer when asking why someone would select an AR-15 in 6mm ARC. The ballistics are tremendous in comparison with other AR-15 cartridges. The bullet retains enough energy to ethically take big game at 400 yards with a minimal bullet drop, something you don’t find in many other AR-15 cartridges.

The caveat comes in the price of ammunition, which is near the top of the price scale. Many 6mm ARC enthusiasts reload to reduce this cost.

6mm ARC - Performance 105 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 2,750 1,763 N/A
100 2,580 1,552 +2
200 2,417 1,362 0
300 2,2260 1,190 8.6
400 2,108 1,036 25.6

6.5 Creedmoor

There is a reason the AR-15 chambered in the 6.5 Creedmoor has taken the sporting world by storm over the last two decades. The caliber shoots flat, drops only 18 inches at 400 yards, and delivers a wallop thanks to its blistering velocity. The 120-grain bullet even handles wind drift better than other calibers while delivering a whopping 1,410-foot pounds of energy at almost a quarter mile. The range, energy, and relatively low cost of ammunition make this caliber the most popular in new AR-15 purchases. Whether you’re big game hunting, long-range varmint hunting, protecting your home, or just plinking, the 6.5 Creedmoor cartridge is the current leader in the AR-15.

6.5 Creedmoor Performance Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 3,050 2,479 N/A
100 2,850 2,164 +1.4
200 2,659 1,884 0
300 2,476 1,634 6.3
400 2,300 1,410 18.3

6.5 Grendel

The 6.5 Grendel is a cartridge with a rapidly growing following. The AR-15 it is often considered the epitome of a varmint gun when chambered in the 6.5 Grendel. Energy, speed, and a flat shooting trajectory nearly equal to the 6mm ARC but offered in a heavier, 123-grain bullet, this is a very popular cartridge.

The 6.5 Grendel retains enough energy to ethically take deer, antelope, and hogs at ranges up to a quarter mile. In a home-defense setting, the AR-15 in the 6.5 Grendel cartridge operates efficiently with little chance of a jam, a characteristic many look for in a platform for personal defense.

6.5 Grendel Performance 123 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 2,580 1,818 N/A
100 2,410 1,585 +1.7
200 2,246 1,377 0
300 2,088 1,191 8.7
400 1,937 1,025 25.3

6.8 SPC

Developed by Remington for long-range military marksmanship the 6.8 SPC is popular with big game hunters as well. The ballistics of the 6.8 SPC resembles the performance of the .270 caliber, arguably one of the best big game cartridges ever developed. The AR-15 chambered in the 6.8 SPC is one of the few AR-15 style rifles that works for both self defense and hunting.

The design of the 6.8 SPC is about halfway between the standard 5.56 and 7.62 mm NATO, the two rounds the AR-15 was originally designed to chamber. As such, it is a compromise cartridge with a lot of potential for anyone interested in getting an AR-15 with maximum range.

6.8 SPC NATO Performance 120 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 2,460 1,612 N/A
100 2,250 1,349 +2.3
200 2,051 1,121 0
300 1,863 925 10.5
400 1,687 758 31.1

7.62x39MM

The darling of the former Soviet Union and still a very popular round worldwide, the 7.62x39 looks on the surface similar to the venerable .308 caliber cartridge but ballistics don’t lie. The 7.62x39 mm was designed for fully automatic use in the AK-47 and similar rifles but has moved to the AR-15 platform as well. You’d never go big game hunting with this cartridge in an AR-15 unless you planned on taking game at very close range. The cartridge works well in an AR-15 but once it leaves the chamber, deficiencies emerge. It drops below the 1,000-pound threshold before 200 yards and has a big drop as the bullet reaches a quarter mile. AR-15 style rifles in the 7.62x29MM caliber are designed for close range shooting.

7.62x39 mm Performance 123 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 2,350 1,508 N/A
100 2,053 1,151 +2
200 1,780 865 0
300 1,535 643 14
400 1,159 479 44

9MM

It’s not a fair comparison to put pistol and rifle ammunition side-by-side on a ballistics chart, but some AR-15s now come with an option to fire either 9mm or .45 ACP pistol ammunition. The function of the AR as a home defense weapon remains viable with lighter-powered pistol ammunition since most of the action will be at a very personal range. The 9mm has an effective range against an assailant of 50 yards and is accurate at that range but quickly drops off at longer distances. The AR-15 chambered in the 9mm is designed for close quarter personal defense.

9mm Performance 124 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 1,175 339 0
50 1,074 2904 1.8
100 922 789 12.1

.308

The second most popular caliber in an AR-15 on the American market is the .308, a hunting cartridge that has moved to the quick action of the semi-automatic AR with ease. The AR-15 chambered in the .308 caliber is more commonly known as the AR-10. Packing a punch on both ends, with a substantial recoil coming with a powerfully performing 150-grain bullet, this caliber is more than enough to bring down any North American big game animal regardless of size. AR-10 rifles in the .308 caliber can be used for large game hunting, self defense and target practice.

The .308 delivers a powerful 1,543 pounds of energy at 400 yards and retains enough power to take game at nearly twice that distance. Best, of all, the case design of the .308 works great with the AR-15’s action.

.308 Performance 150 grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 3,000 2,997 N/A
100 2,772 2,589 +1.5
200 2,556 2,176 0
300 2,350 1,839 6.8
400 2,153 1,543 20

.458 SOCOM

The biggest complaint many shooters have with the AR-15 was the smaller caliber offering in 5.56 and .223 calibers. That’s no longer true with the larger caliber rounds now available on the market, and one of the largest is the .458 SOCOM that can deliver over an ounce of lead from a modified AR-15.

The .458 with a 300-grain bullet is a monster round, delivering over 2,200 pounds of energy at the muzzle, with a wallop-sized recoil to match. The huge bullet is viable to 200 yards, but after that, the energy drops nearly as quickly as the bullet’s trajectory does. A standard 5.56 or .223 magazine will accommodate this large-diameter cartridge, but major modifications in the chamber and barrel need to be made. The AR-15 rifle in the .458 SOCOM is ideal for a day at the range or big game hunting.

.458 SOCOM Performance 300 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 1,845 2,267 N/A
100 N/A 1,507 +3.1
200 N/A 1,012 7.8
300 N/A 742 41.7

.45 ACP

The .45 ACP is the second pistol cartridge offered in an AR-15. The .45 ACP is a legendary cartridge with a long, proud history. It is heavier and has more energy than the 9mm, but it pales in comparison to ballistic performance with rifle cartridges.

The sub-sonic speed of the .45 ACP combined with its oversized, 230-grain bullet delivers a substantial punch. When fired rapidly from an AR-15 the combination provides a deadly option for home defense.

.45 ACP n

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 950 461 0
50 908 421 2.4
100 871 388 17.7

350 Legend

Short-distance power is the draw of the 350 Legend. For the first 100 yards, it delivers powerful energy well in excess of the 1,000-foot-pound limit for ethical hunting. After 100 yards, the energy drops rapidly, and the bullet trajectory plummets as well, dropping almost six feet at 400 yards.

The 350 Legend AR-15 rifle, with an average-length barrel, can deliver devastating power in a home, or self-defense setting. For hunting or longer range target shooting, this is not a good choice.

350 Legend Performance 150 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 2,325 1,801 N/A
100 1,968 1,290 0
200 1,647 905 7.5
300 1,373 629 28.1
400 1,173 452 67.2

.450 Bushmaster

If you’ve got to deliver a lot of lead on a close-range target quickly, the .450 Bushmaster AR-15 might be what you’re looking for. The 250-grain bullet delivers an incredible 2,686 pounds of energy at the muzzle. Within 100 yards this monster of a cartridge will stop a charging grizzly bear or destroy an engine block with equal destructive power.

You’ll feel this round when firing either singly or in quick succession since the cartridge produces a substantial recoil. The ammunition isn’t cheap either and many enthusiasts choose to reload rather than spend the extra money in purchasing boxed ammunition.

.450 Bushmaster Performance 250 Grain

Distance
(Yards)
Velocity
(Feet Per Second)
Energy
(Foot Lbs.)
Bullet Drop
(Inches)
Muzzle 2,200 2,686 2.4
100 1,835 1,868 +4.1
200 1,515 1,274 0
300 1,255 874 19.3

Major Manufacturers of the AR-15

ArmaLite

The original designer of the AR-15 in the late 1950s, ArmaLite sold the rights to the rifle to Colt but returned to the market after the original patent expired. ArmaLite is back in the game, producing a variety of their AR-10 and M-15 rifles, all designed on the original AR platform they first invented.

CMMG

If there’s a caliber of AR-15 you’re looking for, odds are CMMG has one ready for you. CMMG AR-15 rifles are available in the major calibers, along with four pistol cartridges in 9mm, 10mm, 40 S&W, and .45 ACP.

Parts, accessories, kits, and a wide variety of colors make this a universal source for all things AR-related.

Century Arms

Builders of semi-automatic rifles on the AK platform, with pistols utilizing the AR mechanism, Century Arms is devoted to the 7.62x39mm, with a few 7.62x54mm offerings, along with 9mm pistols, and one interesting 12-gauge shotgun in a futuristic style. Century Arms AR-15s also come with a large assortment of accessories and kits.

CheyTac

Standard design AR-15s with match-style stocks and configurations for long-distance shooting sets CheyTac apart from other manufacturers. Offered in .308 and 6.5 Creedmoor models CheyTax AR-15s test the limits of long-distance shooting on an AR-15 platform.

Del-Ton

With dozens of combinations and varieties utilizing the AR platform Del-Ton has remained true to the original calibers of the AR-15 with offerings. Del-Ton AR-15s come chambered in .223 Wylde, 5.56 mm, 7.62x39 mm, and .308 calibers. They offer a wide assortment of AR accessories including muzzle brakes and suppressors.

Diamondback

This Florida-based company features hundreds of AR-15s marketed under their label as the DB-15 series. They also offer pistols, revolvers, and a wide variety of accessories designed to personalize your purchase of one of a Diamondback AR-15 style DB-15 rifle.

H&K

Heckler and Koch sell knives, pistols, carbines, and rifles with many offerings in the AR-15 style. They are one of the market leaders in rimfire AR-15s. H&K AR-15 style rifles featuring many models chambered in .22 Long Rifle, 5.56, .45 ACP and .223 calibers. H&K is a fast-moving, expanding leader in the American firearms market while gaining a worldwide positive reputation.

Kel-Tec

A market leader in innovative design, Kel-Tec AR-15-style rifles employ futuristic designs and are chambered for lighter cartridges. They offer .22 Long Rifle, .40 S&W, 9mm, 5.56 mm, and a unique 7.62 mm offering in a “Bullpup” configuration.

They also sell pistols, shotguns, and accessories for anything that fires a bullet.

LWRC

A high-end manufacturer delivering products with high tolerances at higher-than-average consumer prices, LWRC specializes in carbines, shorter-length rifles, and pistols all using the AR-15 platform. LWRC AR-15s can cost up to three times as much as rival products but are known for their choice of high-end materials, meticulous construction, and customer service.

POF

Longer barrels in lengths from 16.5 to 20 inches combined with cartridges such as 6 mm Creedmoor, 6.5 Creedmoor, and .308 Winchester make POF AR-15s serious long-distance rifles. Pricing for POF rifles is on the upper end of the market, but if you’re looking for a semi-automatic rifle with long-range capability they’re a company worth a look.

Rock River Arms

If you’re interested in the heavy calibers an AR-15 manufactured by Rock River Arms is a good place to start. Rock River Arts offer AR style rifles in .458 SoCom, .350 Legend, 6.5 Creedmoor, and 450 Bushmaster. These higher caliber AR-15s weigh a little more and are costlier than a standard 5.56 mm or .223 caliber, but they deliver a powerful punch.

Ruger

You know what you’re getting with a Ruger AR-15 rifle. It will be high quality, durable, and built to exacting standards, that is the Ruger reputation, and it extends to their line of AR-15 rifles. You expect quality with Ruger, and you always get it from one of the world’s leading manufacturers.

Sig Sauer

Renowned for the quality and variety of pistols they produce, Sig Sauer also builds a high-quality AR-15. They produce one of the finest ambidextrous designs on the market, providing a durable, reliable semi-automatic rifle that will work for everyone. Sig Sauer AR-15s come chambered in 9mm, 5.56, 7.62 and .223 calibers.

Springfield Armory

Top tier out of the box, with included accessories that are extras on the AR-15s made by rival companies, Springfield is known for quality and reliability. They produce rifles to exacting standards and their products last a long time in the field. Experts at creating accurate rifles, Springfield is one of the best on the market. Springfield AR-15s are chambered in the popular 5.56, .223 and .308 calibers.

Windham Weaponry

Versatility is a hallmark of this company. They produce upper assemblies for high-power cartridges such as the .300 Blackout that will interchange with a standard .223 caliber/5.56 mm rifle. The magazines are interchangeable, with the larger .300 cartridges having a smaller capacity but the performance will be the same. They have many different calibers available for similar modifications. Windam Weaponry AR-15 style rifles are chambered in 5.56, 7.62 and .308 calibers.

Conclusion

The world of AR-15 rifles has grown tremendously since the early days of Colt when the .223 was the only civilian caliber available. Now with dozens of manufacturers and hundreds of models of the AR-15 available, the original designers wouldn’t recognize their innovative design.

You can purchase AR-15s in as light a caliber as .22 Long Rifle or in big game crunching powerful rounds like the .450 Bushmaster and the 300 grain .458 SoCom. There are AR-15s for home defense, varmint hunting, plinking, and long-range shooting, with a growing market among big game hunters. There is one out there for you.