What does “AR” in AR-15 stand for?

Hint: It’s not “assault rifle.” Here’s a brief history of today’s Modern Sporting Rifle, including how the original AR-15 nearly failed.

What does “AR” in AR-15 stand for?

Featured Photo: Private Michael J. Mendoza Firing His M-16 Rifle Into a Valley during Operation Cook, National Archives 

Contrary to what many think, the “AR” in AR-15 does not stand for “Assault Rifle.” Neither does it stand for “Automatic Rearming,” “Armed Retiree” or even “Auntie Ruth.” It simply stands for ArmaLite Rifle 15, the company from which it was born. It's how this arms manufacturer named its products. In fact, there have been several AR rifles, including the AR-1, AR-5, AR-7, AR-10, AR-16 and AR-17.

It almost didn’t happen

Given the design’s popularity today, it’s hard to imagine that the original AR-15 could have easily failed. In 1957, ArmaLite had rushed a prototype of an earlier, larger version — the AR-10, a 7.62x57 battle rifle — to the U.S. Army, hoping to secure a major contract. However, during torture testing at Springfield Armory, the barrel of this early AR-10 split open. Army weapons designers, already in development of and lobbying for their own new rifle, the M-14, jumped at the chance to downplay this new rival as a viable alternative. And so ArmaLite — then a division of the Fairchild Engine and Airplane Corporation — went back to work, with legendary gun designer Eugene Stoner, a former Marine, leading a team to design a scaled-down version of the rifle.

The advantages of the newly designed AR-15 were quickly apparent. Using what was then state-of-the-art manufacturing processes and materials like fiberglass, aluminum and plastics — a radical change from standard wood-and-steel battle rifles — the finished AR-15 weighed less than eight pounds with a fully loaded magazine. The M1 Garand, which soldiers had lugged during both WWII and the Korean war, weighed 9 ½ pounds and carried just eight rounds in its magazine. Also, the AR-15 was chambered for a .22-caliber cartridge, which weighs much less than both the standard .30- and 7.62x51mm rounds the Army previously used. Troops could now carry much more ammunition into battle. The AR-15 also kicked less than these older rifles, and it was quite accurate.

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A few necessary tweaks

Of course, there were issues with the new design. The new AR-15 used the same recoil and gas systems as the AR-10, but its smaller size presented challenges. The AR-15 chambered a specially developed .222 Remington Magnum cartridge, which later became the now-standard .223 caliber/5.56mm NATO round. This cartridge produced higher gas pressures in its smaller chamber than did the larger 7.62mm round. In addition, the .223 had a flatter trajectory. ArmaLite engineers had to make provisions in their designs to accommodate those characteristics by modifying both the gas system and sights. Other modifications included a stronger barrel with a two-piece handguard, relocating the cocking lever from under the top carry handle to the rear of the receiver, modifying the safety switch, reducing the magazine capacity from 25 to 20 rounds, and increasing receiver and magazine clearances and a feed ramp modification for better functionality in combat.

AR-15, Photo: NRAMuseum.org

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One year after the Army dismissed the AR-10, ArmaLite sent the new AR-15 to the Army for testing. The response? “The United States Army Infantry Board recommends that the ArmaLite (AR-15) rifle be considered a potential replacement for the M–14,” a 1958 report stated. Still, having just picked up the M-14, the service wasn't rushing to buy any new rifles. Understanding how fickle government procurement processes are and saddled with some financial troubles, ArmaLite sold the rights to both the AR-10 and AR-15 to Colt Industries. Colt began aggressively marketing the rifles to both the U.S. military and foreign entities.

The coolest birthday party ever

In a stroke of good fortune, in July 1960 Colt representative Robert Macdonald showed off the AR-15 to U.S. Air Force General Curtis LeMay at a birthday party for Fairchild's ex-president Richard

Boutelle, where LeMay was allowed to shoot up watermelons in Boutelle's back yard. LeMay was so impressed he pushed the Air Force to buy the rifles for Air Force security personnel.

The Army, however, remained skeptical. And so, while the military continued their tap dance, Colt decided to take the new rifle design to the civilian market. A full-page advertisement in Guns magazine in 1963 declared, “With Colt's new AR-15 Sporter, you're ready for a new hunting adventure. If you're a hunter, camper or collector, you'll want the AR-15 Sporter.” Unlike the military version, these rifles were single-shot versions, but otherwise they were basically the same. The price? About $190. In contrast, back then the average household annual income was $5,807, while a gallon of gas cost 29 cents and a new car would set you back an average of $3,233.

Into the jungles of Vietnam

About this same time, Colt and Defense Secretary Robert McNamara were beginning to convince the Army to give the AR-15 a serious look. The Army was considering a version of the rifle for its still relatively new elite battle troops — known then as the “Special Forces” — as well as Airborne soldiers. The Army designated its version of the AR-15 the M-16A1, while the Air Force called its version the M-16. Colt sold the military the rifles as the “Colt Automatic Rifle 15 (CAR-15),” and the civilian rifles were renamed the “SP-1.” By 1966 both the Army and Marine Corps were issuing M-16s to all troops headed to Vietnam. The rest, as they say, is history.

The first M-16s were not overly popular with many combat soldiers during the early years of the Vietnam War. My friend and colleague Stephen D. Carpenteri was a combat Marine in the late 1960s in Vietnam, where he called the early M-16 the “Matty Mattel” for its propensity to jam at the most inopportune of times. This early problem was the result of the need to keep the rifle clean, and infantrymen were not issued adequate cleaning kits. Also, early ammunition caused massive fouling in this design, resulting in jamming. Later versions of both the rifle and its ammunition helped solve this problem, and the M-16 proved itself to be both accurate and reliable.

A historical precedent

Colt's early decision to market the AR-15 to the civilian marketplace should not be surprising to those today who say that the general populace should not own military-style rifles. Though the technology built into the AR-15 is light years ahead of rifles used by the military of earlier generations, historically private citizens have owned guns similar or identical to military types, simply because that was what was available. And the requirements of war have historically been the driving force behind innovative firearms design.

Many decades, several modifications and variations, and many millions of firearms later, the M-16 continues to serve armed forces personnel from many countries around the world well. Its success has inspired the development of both clones and other small-caliber/high-velocity combat arms. In addition to its widespread acceptance among global military services, the AR-15 is also a favorite of law enforcement agencies and, since the designation of the civilian version as the “Modern Sporting Rifle” in 2009, recreational and competitive shooters as well as hunters. How popular? The National Shooting Sports Foundation estimates that, as of the end of 2015, there are almost 14 million MSRs owned by U.S. civilians.

But “Assault Rifle?” Not hardly.

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