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There have been plenty of famous firearms throughout history, but few have had the lasting appeal of the AR-15. It has been in service since the 60s and continues to see use to this day among military personnel, law enforcement and civilians. Depending on who is using it and the configuration, it may be called the AR-15, the M-16 or the M-4, but we’ll get to that later.

To get the full picture of the AR-15, you need to understand the rifles that came before it. It begins with the company behind the AR-15 as well as the rifle’s namesake, a manufacturer known as ArmaLite.

Before the AR-15: Origins of ArmaLite

The “AR” in AR-15 is short for “ArmaLite Rifle,” despite the misconception some have that it means “assault rifle.” Considering the origins of ArmaLite, you wouldn’t expect the company to design one of the best-selling firearms of all time.

George Sullivan, then the patent counsel for Lockheed Corporation (which is now known as Lockheed Martin), started ArmaLite in 1954. Its headquarters was a machine shop in Hollywood, California, and it’s more than a little ironic that the plans for the AR-15 came in a state that would later attempt to ban it and place all kinds of restrictions on it.

ArmaLite was a subdivision of Fairchild Engine and Airplane Corporation, which funded it. Since the company didn’t have much money and its shop space was limited, it was supposed to stick to creating weapon designs that it could sell to manufacturers.

Sullivan struck gold one day conducting tests of a rifle prototype at the shooting range. By chance, he ran into a man named Eugene Stoner, who designed firearms. Sullivan hired Stoner on the spot, and he quickly became ArmaLite’s chief design engineer.

Eugene Stoner with Mikhail Kalashnikov, designer of another famous rifle, the AK-47


The First ArmaLite Rifles

Shortly after its incorporation, ArmaLite began creating rifles, and its early designs were unique in that they were intended to be broken down into pieces and put back together as necessary. Since the rifles separated this way, they were easy to store in aircrafts, cars and other vehicles, and then assembled when needed in emergencies. In a way, this foreshadowed the AR-15 and how simple it is to take apart and customize.

One reason ArmaLite started designing its firearms this way is because the U.S. Air Force wanted a rifle that it could store in the survival kits of its airplanes. ArmaLite answered the call with its AR-5, a bolt-action rifle that shot a .22 Hornet round. Another benefit was that the rifle floated, which was just what soldiers would need in the event of a water landing.

ArmaLite came out with its AR-5 design in 1954, and the Air Force decided to use it in 1956. Although ArmaLite planned to design civilian weapons, its military success with the AR-5 was huge for the company. This led to its next design, a .22 Long Rifle called the AR-7.

During this time, the U.S. military was transitioning away from its previous rifle of choice, the M1 Garand. Although the gun had been reliable and effective during World War II, its days were numbered. It was over 10.5 pounds and had just an eight-round capacity. That combination of a heavy weight and a low capacity made it a poor choice as warfare evolved.

ArmaLite jumped into the competition to make the military’s next rifle with its Ar-10. Unfortunately, the company was late to the party, and this led to it rushing to hand build two AR-10 models based on the fourth prototype it had created. The AR-10 was going against two Springfield rifles, the T-44 and the T-48.

There was plenty to like about the AR-10, and its features included an aluminum flash suppressor, a gas system, a recoil compensator and a straight stock. The rifle was light, and those who shot it ended up loving it.

That was the good news. The bad news was that the barrel on the AR-10 didn’t hold up to the military’s rigorous testing, and it eventually burst from the pressure. ArmaLite was on it, swapping in a steel barrel that would hold up better, but it didn’t matter. The military selected the T-44 in 1957, which became known as the M-14.

Production Deals with Artillerie Inrichtingen and Colt

Despite not getting that military contract in 1957, another door did open for ArmaLite that year. On the 4th of July, Artillerie Inrichtingen, a Dutch weapons manufacturer, purchased rights to manufacture the AR-10 over the next five years.

The AR-10 had its share of issues, though. Samuel Cummings, an international arms dealer, set up a contract with Nicaragua in 1957. General Anatasio Somoza was the nation’s chief military commander then, and he personally tested the AR-10. When a bolt lug broke while he was going through these tests, that weapons contract was no more.

Artillerie Inrichtingen found several other problems with the rifle, which hampered distribution. It ended up going primarily to Portugal and Sudan.

Two years later in 1959, ArmaLite was in a tough spot. It had its revised AR-10 design, along with a new design for its AR-15. But it didn’t have the capability to produce large volumes of either rifle. That led to a deal with Colt for both of those designs. To ensure that production went smoothly, one of the designers of both rifles, Robert Fremont, went to Colt at the same time.

The Early Success of the AR-15

ArmaLite updated its AR-10 design when it created the AR-15. One of the most significant changes was the caliber, as the new rifle design could accommodate .223 Remington and 5.56 NATO ammunition.

Colt began selling the AR-15 in 1959, but it wasn’t to American citizens or military personnel. The very first AR-15s actually went to Malaysia, which was known as Malaya at the time.

In 1960, there was a demonstration of the AR-15 seen by General Curtis LeMay. He thought very highly of the rifle, and he remembered its effectiveness the next year, when he received a promotion to Chief of Staff for the U.S. Air Force. He put in a request for 80,000 AR-15s.

Also in 1961, Eugene Stoner went from ArmaLite to Colt. Even though ArmaLite stayed in business after that, selling its two best designs in the AR-10 and AR-15 was a major blow for the company. Fairchild decided to dissolve all association with ArmaLite in 1962, and in the 70s, ArmaLite ceased operations. The brand itself would end up going through multiple owners and revivals.

The U.S. Military Adopts the M-16

The Air Force ended up calling the AR-15 the M-16. Despite General LeMay’s enthusiasm over the firearm, there was resistance to adopting it. Chairman of the Joint Chiefs of Staff and General Maxwell D. Taylor felt it was unwise to have rifles of two calibers in use.

After he advised against it, President John F. Kennedy rejected General LeMay’s request for those 80,000 AR-15s. Still, there was a shipment of 10 AR-15s to South Vietnam in 1961, and a positive response led to another shipment of 10,000 in 1962.

Soldiers thought very highly of the AR-15, and it seemed to be the best choice for the rifle of the U.S. military. It took time, though, because many in the military were set in their ways and didn’t want to see the AR-15 replace the M-14, leading to biased testers performing comparisons of the rifles.

Circumstances would eventually force the military’s hand. The M-14 was leaving troops outgunned by opposing forces wielding AK-47s, and at the beginning of 1963, it was determined that M-14 production couldn’t meet what the military would need going forward. M-14 production was halted, and the M-16 became the universal infantry weapon across all branches of the U.S. military. Rifles in the M-16 configuration were first used in 1965.

Unfortunately, there were issues with the M-16 which cost the lives of many of our troops in Vietnam. Among such issues are failure to extract spent cartridge cases, light primer strikes, excessive wear, and parts breakage.

But the topic of the M-16’s malfunctions is too broad to cover that to do it justice, we’ll write a separate article on it. For now, if you’d like to learn more, you can reference this blog post from our source. Suffice it to say that not enough testing was done before the first M-16 rifles were approved for use in Vietnam.

Continued Military Use: From the M-16 to the M-4

At this point, it’s important to clarify what the difference is between the AR-15, the M-16 and the M-4.

The AR-15 is the civilian version of the rifle. Colt owns the trademarks to the term AR-15, but its patents on the weapon’s design expired in 1977, which means the same type of rifle is made by many manufacturers.

The M-16 is the first military version of the AR-15. There have been three versions of the M-16 – the original M-16, the M-16A1, the M-16A2 and the M-16A4, each with updates to improve the rifle. The rifle is still in use to this day.

Why was there no M-16A3? The most likely reason is that between the A2 and the A4, the military was looking for a lightweight carbine with a shorter barrel that would be more effective in tight spaces and for close-quarters use.

That led to the creation of the M-4. The M-4 has been steadily replacing the M-16, and most of the U.S. military now uses it. Although the shorter barrel can limit long-range accuracy, with the right scope and rifle configuration, M-4s and AR-15s with carbine-length barrels can hit targets at 500 yards or more.

The AR-15 Becomes America’s Most Popular Rifle

Colt sold the AR-15 to civilians since the 60s, but the rifle became far more widespread once the company’s patents expired and other manufacturers could get in on the action. The rifle was especially popular from 1989 to 1994, but 1994 saw the passing of the Federal Assault Weapons Ban.

The ban was an attempt by the government to prevent mass shootings. It made it illegal for civilians to purchase firearms classified as assault weapons, including the AR-15 and the AK-47, although assault weapons that people already owned were grandfathered in and considered legal.

Prices for pre-ban AR-15s skyrocketed, and manufacturers had to start making AR-15 variants without the key features that made the government consider the AR-15 an assault weapon. The government didn’t renew the ban when it expired in 2004, and the ban itself didn’t have a significant effect on gun violence statistics.

Since the ban expired, there have been attempts to ban the AR-15 and similar weapons again, especially after shootings occur. However, none have been successful, and the AR-15 remains the rifle of choice for many Americans.

There are quite a few reasons for why the AR-15 is so popular, chief among them its versatility and performance. It can deliver a high rate of fire while remaining accurate at short, medium and even long ranges.

Depending on your AR’s setup and your choice of ammunition, it can work well for shooting competitions, home defense, hunting or simply enjoying yourself at the range. It’s easy to field strip and swap out parts, making AR-15 customization and building both very popular.

The AR-15 and its variants have a rich history in both the military and civilian markets. The fact that it has been around for over 50 years and it’s still the military’s rifle of choice is a testament to the quality of its design.

A firearms and ballistics enthusiast and an outdoorsman, Mike is one of Gun News Daily's best contributing authors. He's a researcher, data analyst and writer by trade and strongly adheres to conservatism—a stalwart of the right to keep and bear arms.


  1. Nice article. There is an error is in regard to the M16A3. The A3 is astheticly identical to the A2. The difference is the firing mechanism. The A3 is full automatic not three round burst as th A2. I believe the (mass) confusion is due to Colt’s (A)R6721 designation as the AR-15A3 “flattop.” Many AR manufacturers use the A3 designation for flat top rifles.

  2. Great article. Full story told. I have owned 5. I still like full butt stock best. You can butt stoke with it if need be.

  3. M16 was select fire – Semi Auto – Full Auto with Triangular hand guards and 3 prong flash hider
    M16A1 was select fire – Semi Auto – 3 round burst (as requested by the Marine Corps) with Triangular hand guards bird cage flash hider. And this was accurate to 500 yards with iron sights.
    M16A2 was select fire – Semi Auto – 3 round burst with interchangeable round hand guards. (So much nicer) improved bird cage flash hider.
    M16A3 was limited issue – semi auto – full auto.

    • I was in the army from 1979-1985 and my MOS was 45B, Small Arms Repairman. After working on and inspecting a couple of thousand of M16A1s, I can tell you with certainty that they DID NOT have 3-round burst capability. They were semi-auto and full-auto, with no other firing mode, and I’ve actually fired them in both modes. BTW, some people were using the 3-prong flash-hider on the original M16s to break the bands on cases of C-rations. They bent the barrels doing that, and the M16A1 had the birdcage style flash-hider to prevent it. I was told that by my instructors who were army and marine corps Vietnam veterans who used the old M16s, but it’s not the official explanation. I also saw 1 H&R M16A1 and 1 GM Hydra-Matic M16A1 while in basic training. The H&R was originally stamped AR15, and the lower receiver was an odd kind of glossy brown-gold-purple color after many years of wear.

      Manufacturers: Colt Manufacturing, Harrington and Richardson, Hydra-Matic Division of General Motors
      Length: 39.625 inches
      Weight (without magazine and sling): 6.55 pounds
      Weight (with loaded 30 round magazine and sling): 7.96 pounds
      Bore Diameter: 5.56mm (.233 inches)
      Rifling: Right-hand twist, 6 grooves, 1 turn in 12 inches
      Maximum Range: 2,653 meters
      Maximum Effective Range: 460 meters
      Muzzle Velocity: 3,250 feet per second
      Rate of Fire (Cyclic): 650–750 rounds per minute
      Rate of Fire (Sustained): 12-15 rounds per minute
      Rate of Fire (Semiautomatic): 45-65 rounds per minute
      Rate of Fire (Automatic): 150-200 rounds per minute

  4. I went in the USAF in 1979…….. We had M-16s YET they were stamped AR-15 made by Colt. and were Select Fire. SAFE/SEMI/ Rock-N-Roll AKA Full AUTO.
    The one I was first issued had a Three prong flash suppressor/hider, and the triangle hand guards.
    The M-203 could and was attached and replaced the triangle hand guards for use with fire teams.

    1980-81 (some where in that time frame) I was issued a different M-16 AGAIN stamped AR-15 made by Colt, with triangle hand guards and bird cage flash suppressor/hider and it was also Select Fire/Safe/Semi/ Rock-N-Roll/ AKA FULL AUTO. Again the M-203 could be and was attached at times.
    We also had the GAU. It had a shorter barrel collapsible stock and 4 inch flash suppressor/hider that was issued to certain personnel. The military/Special Forces had experimented and used shorter variants over the years…..with various designations….. but that is for another time.

    In 1982-83 they were still working on/developing/perfecting the SAW…….A Squad Automatic Weapon that would fire “the same ammunition” the M-16 fired. It also had different parameters for performance vs “the old M-16″…. a tad bit longer range. To make the SAW work they needed/went to a heavier bullet.
    Using this heavier ammunition in the THEN M-16 accuracy left MUCH to be desired, “one could not hit the broad side of a barn” so to speak.
    The same applied to using the standard M-16 round/ammunition in the SAW.

    The ORIGINAL M-16 fires too fast on Rock -N-Roll/ AKA Full Auto. One must learn proper trigger control in order to use it effectively. Takes time and ALOT of ammunition

    With the M-16 on Rock-N-Roll/ AKA Full Auto, One can load 10 rounds in a magazine and aim at a target 100 meters/yards away, squeeze and hold the trigger down. The last bullet will hit the target before the first empty shell casing hits the ground. Needless to say this also means a shorter barrel life.

    To make the SAW round work with the M-16 they had to change the rifling in the M-16 Barrels.
    This brought about the NEW AND IMPROVED M-16 WITH Round hand guards/ New rifling/and the bird cage flash suppressor/hider.

    The Three Shot Burst model was suppose to shoot a 2 MOA at (IF I REMEMBER CORECTLY) 800 Meters and
    penetrate both sides of a steel pot at 600 meters. I may that backwards as I was never issued/fired or carried one.

    There is confusion within the History of the Rifle and Military versions being stamped AR-15s.
    The Civilian models also being stamped AR-15 that are only Semi Auto….is a start………

    As to which model is actually the A2-A3 I leave it to you decide.

  5. So I am a little confused. The troops (US ARMY) in So. Vietnam used AR15s? Were they semiautomatic like the civilian version? I always thought the AR15 was always civilian version and semiautomatic only.

  6. I served with 2/26 Marines ’66 & ’67 in the I corps area of Viet Nam. Half way through our tour the M16 replaced the M14. We had major issues with the M16, it would double feed because the bolt was defective. We lost lives and opportunities because of this. It came to a point that we taped our cleaning rod to the forearm to clear the lodged cartridge in the chamber. It was such an issue we had congressman come over to access the problem. Colt issued new redesigned bolts and the problem was fixed. It was not a problem with cleaning the M16 as stated in your article. I cannot understand where this came from as the issue was a defective bolt. It is too bad that the M16 was sent to Viet Nam without being tested properly.

    • Jim. First of all, I’d like to thank you for reading through the article. Second, on behalf of all GND staff, I want to thank you for your service in the military, especially in Vietnam. And lastly, thank you for pointing out that oversight on our part. I did some research and found out that you were correct. We’ll add more relevant info to the article.


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