What Does AR Stand For? (Hint: It’s Not “Assault Rifle”)

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What Does AR Stand For? Well, it can stand for a lot of things. There’s augmented reality, artists and repertoire, and Arkansas. There’s also Axl Rose, Al Roker, and Pope Benedict XVI, otherwise known as Alois Ratzinger. When regarding rifles, though, specifically the AR-15, AR does not stand for “assault rifle,” as many people believe—nor “automatic rifle” for that matter. So, what does AR stand for? Read on.

What Does AR Stand for When It Comes to the AR-15?

The “AR” in AR-15 stands for “ArmaLite Rifle.” ArmaLite is the company that designed and developed the AR-15. It was the rifle division of an aircraft company called Fairchild in the 1950s. They designed other rifles, like the AR-5 and AR-7 survival rifles, and used this naming style repeatedly. Today, ArmaLite still exists, along with a bunch of other companies that make civilian AR-15s. But the history of the AR-15 name and what is and isn’t an AR-15 is a little complicated.

What Does AR Stand For: Table of Contents

  • The Early Days of the AR-15
  • The AR-15 Becomes the M16, Then Becomes the AR-15 Again
  • AR-15s for Hunting
  • Why Some Think AR Stands For “Assault Rifle”
  • Frequently Asked Questions

The Early Days of the AR-15

The AR-15 was developed by ArmaLite in 1956 when designers started experimenting with lighter materials and ammunition for service rifles. It was a 6-pound, select-fire, air-cooled rifle made from cutting-edge materials for the time—aluminum and plastic composites. Its designer, Eugene Stoner, built the AR-15 at the request of the U.S. Continental Army Command (CONARC). Stoner scaled down his AR-10 design—chambered in 308 Win.—to fire the 223 Remington. Then ArmaLite submitted his prototype for testing.

reproduction of Eugene Stoner's original AR-15
A reproduction of Eugene Stoner’s original prototype for the AR-15 made by Brownells. Brownells

CONARC found the AR-15 to be extremely capable. Soldiers could carry three times more 223 ammunition than they could 308, giving a seven-man team as much firepower as an 11-man team armed with the current service rifle, the M14. But higher-ups in the Army vetoed the design, pushing ArmaLite’s parent company, Fairchild, to ditch the whole project and sell the AR-15 and AR-10 designs.

Colt bought the rights to both rifles for $75,000 plus a 4.5 percent royalty on future AR-15 sales. They developed two versions, calling them the Colt Model 601 and 602, and shopped them around to militaries all over the world.

The AR-15 Becomes the M16, Then Becomes the AR-15 Again

Salesmen at Colt eventually got the rifle in front of the U.S. military again. They brought a few Model 601s to General Curtis LeMay, Airforce Vice Chief of Staff, at a birthday party. During the festivities, they shot some watermelons. Everyone was impressed, and Colt sold a bunch of rifles to the Air Force.

The Army continued testing the rifle in more formal settings, and there was a lot of back and forth between military leaders about the 601 and 602 as they geared up for the Vietnam War. It was a space-age gun that didn’t look or feel like anything that came before it. There was also the logistical problem of introducing a new cartridge into an army that was already set on the 308. But after hearing reports that the M14 would leave soldiers under-gunned, Secretary of Defense Robert McNamara ordered its adoption and 85,000 new rifles from Colt. The rifle was re-named the M16.

Make no mistake, Stoner’s original AR-15 and the Colt 601 and 602 were select-fire, fully-automatic rifles designed to be the baddest gun in the land—what many would call an assault rifle. But once Colt saw the success of their 601s and 602s as the M16, they felt that a semi-auto-only version would also get the attention of civilians and law enforcement. In a move that seems to make no sense at all, they decided to call these civilian semi-auto rifles AR-15s.

AR-15s End Up in the Hands of Hunters

Today, the AR-15 is one of, if not the, most popular civilian rifle in America. Once Colt’s patent ran out in 1977, dozens of companies started making rifles based on the semi-auto version of the AR-15. Because the rifle gained popularity under Colt and the AR-15 name, consumers called AR-pattern rifles made by all manufacturers AR-15s. (It’s similar to how people describe all Colt 1911 clones as 1911s today.)

The military M16 and M4 rifles also helped boost the popularity of the civilian AR-15. Soldiers returning from war and re-entering civilian life since the 1960s were familiar with their service rifles and wanted to take something similar to the woods. This is not a new phenomenon. One of the big reasons the 30/06 took off as a hunting cartridge in the U.S. was because soldiers from WWI, WWII, and the Korean War were familiar with it. Veterans and consumers have also been buying military surplus rifles and converting them to hunting rifles for decades.

In the early 2000s, the industry took notice of this and began producing AR-15s and AR-10s chambered for a variety of hunting cartridges. They also configured AR-pattern rifles for the woods with things like optics rails, shorter magazines, and camo paint jobs. Today, the AR-15 and AR-10 are chambered for over 100 different cartridges and used for hunting everything from varmints to big game.

A hunting AR-15 made by Wilson Combat
A Wilson Combat Hunter model chambered in .375 SOCOM. Wilson Combat

Why Some Think AR Stands For “Assault Rifle”

Once a name makes its way into pop culture, it takes on a life of its own. As the AR-15 gained popularity through the 80s, 90s, and 00s, many thought the AR-15 stood for “Assualt Rifle 15” or “Automatic Rifle 15.” It was an easy-enough mistake. Before the Internet, who else but gun nerds and a bunch of generals knew the history of ArmaLite, an otherwise obscure military contractor? AR-15s are also dead-ringers for their “assault rifle” counterparts the M16 and M4. And while civilian AR-15s are semiautomatic, not fully automatic, many hear “automatic” and assume AR stands for “automatic rifle.”

Stoner’s version of the AR-15 and the M16 fit the bill for what’s commonly defined as an assault rifle. They are select-fire weapons that fire intermediate cartridges (short cartridges with characteristics between a handgun and rifle load and an effective range of around 500 yards).

photo of StG-44 assault rifle
An original German StG-44, the first “assault rifle.” Rock Island Auction Company

The term “assault rifle” has roots in WWII, specifically Germany. The Nazis developed the first assault rifle, the StG 44. It was a fully automatic rifle chambered in 7.92×33mm Kurz, a short version of the 7.92×57mm Mauser, and it gave soldiers the same advantages an M16 gives soldiers today—less recoil, sufficient power, and the ability to carry more ammo.

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The 44 stands for 1944, the year the rifle was conceived, and StG stands for Sturmgewehr. Roughly translated, sturm means storm, and gewehr means rifle. “Sturm” can also mean “assault” when used in this context, making the Sturmgewehr an “assault rifle.” Other rifles based on the philosophy of the StG 44, like the AK47 and the M16, are also called assault rifles.

Today, the AR in AR-15 still stands for ArmaLite Rifle, even though Colt popularized it. Only some are still made by ArmaLite, and most aren’t built to the specifications of Eugene Stoner’s original design. While they may fire intermediate cartridges, legal civilian ARs aren’t fully automatic and as such aren’t assault rifles.

What Does AR Stand For: Frequently Asked Questions

What AR-15 does the military use?

The U.S. military does not use the AR-15. Instead, they use modified versions of ArmaLite’s original design for the AR-15—the M16 and M4. Through the years, the military has adapted the rifles for different purposes. Currently, the U.S. Army service rifle is the M4A1 Carbine. It’s a select-fire, air-cooled rifle with a 14.5-inch barrel.

What is the difference between an AR and an AK?

We’ve covered what the AR stands for in terms of the AR-15. The AK in AK47, AKM, AK74, and all other AK pattern rifles stands for Avtomat Kalashnikova. Translated from Russian, this means “automatic Kalashnikov,” referencing the rifle’s semi- and fully-automatic action and its designer, Mikhail Kalashnikov. The AR-15 and all AK pattern rifles are completely different in design and function.

What is the difference between the AR-15 and the M4?

This really depends on which AR-15 you’re talking about—the original prototype from ArmaLite or the civilian AR-15 designed by Colt. From the factory, both rifles have longer barrels than the M4. Civilian AR-15s are semiautomatic while the original prototype AR-15 and the M4 can fire on full auto. Some civilian Colt AR-15s and ArmaLite’s original AR-15 also didn’t have the collapsable/adjustable stock that’s found on the M4.