History of the Colt AR-15 Rifle

Colt fit and finish

Many of the great firearms in history underwent a protracted development period. Most were slow to gain acceptance. The Beretta 92 and GLOCK pistols, for example, faced an uphill struggle. The Johnson rifles were interesting rifles never quite caught on.

Many of those using the AR-15 rifle today do not realize how old the original design really is and how tough the development and acceptance of the Colt AR-15 really was. But good rifles are often long-lived.

The Lee Enfield, as an example, fought the Zulus prior to 1900 and was on the front line in Korea. It is still a fixture of the Canada Rangers. The history of AK rifles speaks for itself. The AR-15 rifle is another legend.

The AR may be nearing middle age, but its most important improvements are pretty fresh. The AR-15 is a sophisticated system that performs well. It is easy to maintain and quite accurate.

Initial Developments

Many of the rifles in use in training our young warriors are older than the soldiers using them. (Rifles on the front line are a different matter.) Yet they continue to serve. The rifle is the first choice of top-notch security teams and armies.

Note the Israelis have their own Galil and thousands—perhaps hundreds of thousands—of captured AK-pattern rifles. They seem to prefer the AR-15 types. Those of us that have a choice of any weapon system most often choose the AR rifle.

The rifle was developed by Eugene Stoner and the contract was awarded to Colt to produce the rifle. The M16 was designed as a counter to the fully automatic AK-47 rifle. The AR cartridge was developed from a high-velocity varmint round, the .222 Remington.

Low recoil, longer range than pistol caliber carbines, and control in fully automatic fire were important parts of the Stoner design.

Colt AR-15 in action
This young Major is firing the Colt AR-15 carbine and finding it good.

Early Errors and Problems

The AR is gas-operated. The gas doesn’t operate by a piston—at least in the vast majority of the rifles—but the gas is led directly to the bolt in this gas impingement system.

When the rifle was issued in Vietnam, the lightweight, accuracy, controllability and easy firepower were greatly appreciated. Soldiers on long patrols could carry a lot of ammunition.

But Army Ordnance made a grievous error (that Congress later concluded verged on criminal negligence). The original 5.56mm loading was developed for a clean burn and high energy.

The Army specified that the same ball powder used in the 7.62mm NATO cartridge be used in service ammunition. The result was a different pressure curve and clogged gas ports.

Worse, after the problem was identified, the Army did not withdraw the ammunition from service in Vietnam. The AR was not originally issued with cleaning gear! Even the original low-maintenance rifle, the M1 carbine, needed cleaning frequently.

The Army entered into several knee-jerk fixes. One was to issue cleaning kits and a comic book-type cleaning manual.

Original Colt HBAR AR-15
This is an original Colt HBAR.

Modifications and Improvements

Colt was asked to modify the firearms to function with ball powder-loaded ammunition. The problem was met with a recoil device with an “internal plurality of masses” that was geared for the ball load. They also increased extractor tension to help in extracting the cartridge.

In some cases, the cartridge case would stick in the chamber—sometimes during combat operations. Was the Colt AR-15 that was designated M16 sent into combat prematurely?

Probably not, but the system was castrated by the poor choice of ammunition and insane lack of cleaning gear. The M16 was developed into a reliable firearm, but at one time was not as highly regarded as it is today.

The short-barrel designs, such as the CAR 15 and others, demanded more development and did not work as well as the later short barrel rifles. The XM177, as an example, demonstrated stupendous muzzle flash. Sufficient gas volume was not generated.

The XM177 rifle, however, used the first telescoping stock on an AR.

Colt History - Sig Sauer ammo
SIG Sauer ammunition gives shooters the edge in a modern AR-15 rifle.

The Modern Colt AR-15

Today, the 14.5-inch barrel M4 is a fast-handling rifle that has proven reliable in action. The 16-inch barrel carbine is the shortest legal length for civilians without jumping through a lot of hoops, paperwork and expense.

In between the M16 and the M4, the AR rifle went through several modifications. Some of these were related to ammunition performance. The 5.56mm load was found to offer excellent wound ballistics against lightly clad Viet Cong. Performance falls off past 100 yards.

The universal adoption of the rifle as a front-line rifle rather than a special-use firearm for jungle combat led to the M16A2. This rifle features a different barrel twist to stabilize the 62-grain load.

Heavier than the original 55-grain loading, the 62-grain bullet offers greater penetration against heavy web gear that might be encountered in Europe. The M16A2 features improved sights and excellent performance. This rifle is simpler to the Colt HBAR released for civilian sales.

The HBAR is still a viable, useful and accurate rifle.

During this time, Colt continued to offer the AR-15 rifle for civilian sales, and they were the first to do so. The original Colt Sporter and the HBAR were popular rifles. The standard 16-inch carbine is popular, and the first flat-top rifles for mounting optics followed.

The inexpensive Colt Expanse was not as well-received. Cheapening a product built on a reputable name isn’t always a good idea. The Colt M4 SOCOM is as close to the military-issue rifle as possible. Colt rifles have set the standard for reliability for many years.

The rifles work as designed and demonstrate a high level of performance. While I own several good rifles, the Colt is my go-to rifle and has been for some time.

Colt AR-15 Close Up
This name means something to many of us.


Recently, Colt announced that they are cutting sales of AR-15 rifles based on “sagging sales.” There are many cheaper AR-15 rifles available. and there are also many highly developed, superbly fitted and accurate rifles that do not bear the Colt name.

Colt has been through hard times before and will probably withstand the storm. Just the same, it may be a good time to grab the Colt you have wanted while you are able. It is, after all, a piece of history.

What do you think of Colt’s AR-15? Do you agree with their decision to cut Colt AR-15 sales for citizens? Let us know your thoughts in the comments below.

About the Author:

Wilburn Roberts

When Wilburn Roberts was a young peace officer, he adopted his present pen name at the suggestion of his chief, as some of the brass was leery of what he might write. This was also adopted out of respect for families of both victims and criminals. The pen name is the same and the man remains an outspoken proponent of using enough gun for the job.

He has been on the hit list of a well-known hate group, traveled in a dozen countries and written on many subjects, including investigating hate crimes and adopting the patrol carbine. He graduated second in his class with a degree in Police Science. It took him 20 years to work himself from Lieutenant to Sergeant and he calls it as he sees it.
The Mission of Cheaper Than Dirt!'s blog, The Shooter's Log, is to provide information—not opinions—to our customers and the shooting community. We want you, our readers, to be able to make informed decisions. The information provided here does not represent the views of Cheaper Than Dirt!

Comments (22)

  1. I was dropping 750 lb bombs at the battle of Ia Drang. It almost makes me cry to hear of the ammo our brave troopers used was causing jams. So very sad!

  2. This article does not get it anywhere close to right. BO, in his 11/08/2019 response and comment has it correct, but leaves out one important step. Colt, once they bought the rights from Fairchild/Armalite, developed the Colt 601, and eventually 602 models. These two design variations were a military “hardened” variant with the addition of full auto capability. These became the M-16. Colt put the old AR-15 design on the shelf for a while before deciding to take a chance on the civilian (mostly hunter) market of the 1960’s. The AR-15 was slow to take off. The AR-15 has never been used by the American military. Even though Armalite had a great idea, it took Colt to give it the design mods that made it attractive to the military.

  3. The problem I have with this article is that the author neglected what I consider to be important history of the weapon in his research. According to the excellent tome “Small Arms of the World” by Joseph E, Smith Ninth Edition, © 1960, 1962, 1966, & 1969, concerning the origin of the AR-15, it was designed by Eugene Stoner, that part he got right, but Stoner was working “for the Armalite Division of Fairchild Engine and Airplane Co.. The rifle was adopted by the Air Force as the M-16. In the interim Colt’s Patent Fire Arms Manufacturing Co. Inc. purchased the manufacturing rights to the weapon…”
    But, and I quote “The M-16 was originally known as the Caliber .223 AR-15 and followed (emphasis mine) a similar rifle chambered for the 7.62 NATO cartridge known as the AR-10. The AR-10 was produced for a time at the Dutch Government arsenal-Artillerie Inrichingen- at Hembrug, Zaandam on a contract basis. It was not used by the Dutch government. The AR-15 was essentially the same as the AR-10 when first made by Armalite, but a number of changes, including a bolt retracting handle mounted at the rear of the receiver rather than on top and a different type of handguard were made in the rifle before it was adopted by the Air Force.”
    That’s right, the AR-10 came first and the Air Force had the M-16 before the Army did.
    Again, I quote, “The United States Army tested the AR-15 and adopted it as the M-16A1. The principal difference between the M-16 and M-16A1 is the presence of the plunger mounted on the right rear side of the receiver. The plunger is used to push the bolt forward if it becomes stuck due to dirt in the receiver.”
    All of this information was gleaned from Small Arms of the World, page 650.
    I was a medic on a Recon team that also was trained in Search and Rescue when I was overseas someplace back in the early 70’s. I seem to have forgotten where we were and were not,(I am 69, after all.). As a Medic, I was issued, thankfully an M1911A1, because the only medics who did not carry weapons were Conscientious Objector draftees and I enlisted. I scored expert with all the weapons with which I qualified and was grateful that I did not have to carry an M-16. Did not like it at all. If you looked at it wrong, it jammed. Check out the history of the battle of Ia Drang. Many men died because the thing jammed in the heat of battle. More than one man was found dead, with his weapon torn apart to find the cause of said jam.
    Today, I do own an AR-15. I have two uppers for it in different calibers and it is a great varmint gun and close up deer rifle. I am reluctant to try to bring down a deer with a 55 grain slug at distances greater than 100 yds because I know people who lost deer trying to shoot them at 150-200 yds. Where I am hunting, I won’t have any shots over 75 yds. The AR should do just fine.

  4. Colt M4 should COLT keep selling to civilian? Absolutely!!! Every American should have a AR-15 by there bed side on the wall in a safe anywhere in the house. It’s America’s rifle and American rifles should be bull in the USA (COLT)
    Sales might not slump as bad it colt could cut there price. S&W can do it $600.00 versus $1000.00+
    Personally I love my COLT M-4 and my 1911 but would also love to have future generations have the opportunity to love COLT also.

  5. When I got out of the service I was fairly burned out on the AR platform. Found an immaculate hbar sported match quite similar to the one pictured above at a great deal. It’s a ban era which means there are some significant differences considering the lower and the bolt but I love it to death. I’ve had it for over a decade now and it still gets carried up into the hills quite often. It reminds me heavily of the MA16a2 I carried in Iraq. It’s heavy, unique, and quite long by today’s standards yet performs like a dream. Occasionally I’ll find my way into a range and this is the one that always has people stopping to take a peek. I’ll let most of them give it a try and it never fails to produce a smile. A superbly well made firearm that I’ll keep until I’m too old to shoot, then I’ll give it to my boy.

  6. I believe colt made the wrong decision to stop selling civilian versions of the AR15. The reason that they claimed to have done has been debated back and fourth until everyone is blue in the face. I believe that the reason they did it was not the mistake that was made. The mistake was the timing of the announcement. At a time in our country when the second amendment is under so much attack, we need our proud American arms manufacturers to stand united. Colt is an American icon in the gun community. They should be setting the example fo Americans to follow. Never forget, our right as civilians to keep and bear arms is not to be infringed. That amendment was written at a time when the civilian population was equipped with the exact same fire power as the military. Colt needs to carry on that tradition and keep the civilians as armed as the government that serves them! Isn’t that the whole point? My two cents, thanks for reading.

  7. Comment or on Colt having cleaning kits for military dead on.
    First AR, M- 16 I seen were those being tested by Spec Forces at Ft. Bragg N. C., and not one of the shortish they had was worth a dam, good for RED’s officers, he’ll Spec ops were using of Korean War M 1 Carbines, same as given to South Viets militar, old Thompsons, German, French and Sweed autos, many stolen after confiscation during Dominican Republic bull crap lies.
    Many a grunt in early Viet years had been trained with M-14 but all of a sudden were given an M-16, most military then and now are crappy marksmen to begin with never mind during SHTF times.
    Colt is building export model AR’s under military contract, lots and lots of them.
    Part of reason being they can build them cheap and make a few Billion$.
    The AT of Bam time had quality issues and Colt knew it but did not give a fly’n pig until Senator Ted Kennedy threatened owners with jail time.
    Have an early 1960 civilian version, had to be registered under 1970’s by WA State law, grandfathered due to closeness of full auto M-16, darn thing was lucky to print 5-6 inch groups with military or civilians 223.
    Cannot legally change original by adding civilian legal uppers with better twist and more accurate barrels, but darned if I would ever buy a Colt of any kind today.
    Lots of great built AR firms today, that put Colts to, “loss for word”, as you can’t shame Colt factory owners.

  8. I feal you really shorted this artical and readers of some of the facts as the actual twist rates then to now along with the facts that the early barrels were not chrome lined, which helped cause spent cartridges stick in the chambers. The early barrels twist rate caused bullets to be unstable and tumble. A couple of early Vietnam vets told me thats how the nick name jammin jimmy came to be becouse of stuck spent cartridges.

  9. Interesting history; thanks for pulling it together. One note, though: Israelis “chose” the M-16 because the US dumped a bunch for free in the ‘80s. Any front line soldier who had an actual choice chose the Galil; MUCH more reliable especially in the desert. M-16s went to support and non-combat units. I hear that in Afghanistan, when our allies are offered free M-4s, they stick with their AKs.

  10. Colt has a history of discontinuing it’s most famous, iconic and best selling guns – the Python comes to mind. Colt has a tremendous advantage apropos the AR15, but has long since given up the lead to lessor known rivals when it comes to refining, improving and customizing the platform. Seems that Colt’s business plan is to get government contracts, avoid investing in r&d, and ignore the retail market. Sadly, Colt is oblivious to the power of brand recognition in the firearms market.

  11. In re: “Recently, Colt announced that they are cutting sales of AR-15 rifles based on “sagging sales.” ”

    My recollection is that because of “sagging sales” of civilian rifles they were cutting “production” of civilian rifles not “sales.” Their sagging sales was causing inventory to pile up so they were cutting production. If Ford sales start “sagging,” dealers slow down on orders, vehicles start piling up in the factory lot and management begins cutting overtime and maybe even an entire shift. You can’t keep building them if they’re not selling.
    Not a knock on Colt, but there are so many good rifles out there priced around $600 that buyers find it hard to shell out $1,200 to $1,500 for a Colt.

  12. According to what I have read Colt is making plenty of ARs in 7.62×39 to sell to foreign countries. The new weapon features a modified receiver to accept the standard AK-47 magazine so the many countries they are selling to won’t have to change their large supply of old magazines. It will replace thE aging AKs that were much less accurate and cheaply made of stamped steel. Ask any soldier and 99% would prefer a AR that shoots the larger round except maybe for long range recon where the ability to carry more ammo may be more important. As I understand Colt is not offering this more powerful rifle in the US but it will undoubtedly end up in the hands of our enemies. I view this as treasonous and I for one will not purchase another Colt. I hope they find the bankruptcy they deserve

  13. The original (and current) AR-15 gas system is not “direct impingement”: Gene Stoner said so. It is a gas piston system; what is innovative is that the gas piston is the bolt, and the gas cylinder is the bolt carrier. When the gas enters the bolt carrier via the carrier key, the gas pressure “inflates” the carrier (think balloon), causing the gas to push the carrier rearward and the bolt forward. Of course, the bolt can’t move, though the gas pressure, pushing forward on the bolt, does “unload” the bolt lugs somewhat as the carrier’s rearward movement begins to cam the bolt to unlock it.

    The gas system is a piston system; the piston is internal (the bolt) and hidden from sight. If we’d started with external systems, such as the FAL, we might now have internal piston conversion kits and shooters would ooh and ahh about the simplicity of the design.

  14. Year was 1968, Ft Jackson… rifle of issue..M-14. I used that up to 1969 my first tour in Vietnam. I did love it…Then had it removed from my hands and given the M16…was not so much in love at first grew on me. Could carry more ammo, the flash suppressor could open any beer can and it was lighter. I kept it clean and had no real issues other than having to open the charging handle if there was water in the barrel.

    Present time… I now have 4 AR platforms… 2 that I built… 223/5.56, 300 aac, and a 7.62×51 (308).. First one I bought was an AR15 H-Bar but was ticked as I wanted to utilize it in Ceremonies with our Vietnam Veterans Org… NO darned bayonet lug. After calling Colt and complaining to their upper office (Never knew of any Bayonet deaths here) because they cut the lugs off. I went to a gun show in Pittsburgh and became the owner of a full upper receiver of a pencil m-16 ….with lug. Since than I am a fan. Quality and dependability are in the eyes of the owner… their preferences and usage. Now one of my Bucket List guns is to buy an M14.. but that will come. Until then I will enjoy building, changing and shooting what I have.. Ya’ll be safe.

  15. In 1977 the Army was obsessive in its cleaning of the M16, to the point where we were encourage to buy pipe cleaners to run through the gas tube as far as they would go. The only model I ever used in an infantry unit had a windage only adjustable rear sight.

  16. Im very disappointed. I think Colt should listen to us die hard consumers and keep building civilian market rifles. Colt needs to make its rifles compatible with todays market. I know rifles are cheaper now and Colt should follow and set a stronger standard.

  17. I in my personal opinion do not like colts ARs only because they are expensive and cheaper quality than many other manufacturers i got a basic rifle at Olympic Arms and built it to my design love it now

  18. To me sagging sales must be from people belief that colt ar’s quality was flagging. Especially for 12-1,500.00 $. There are so many other options and choices… I sold the expanse at retail and a couple were not assbled well at all. The expanse isnt the only firearm from A manufacturer that has had issues. Anyway, i have 2 Colt 1911’s and love them. The oldest one is the best one. The newer series 80 isnt perfect but it runs well enough to carry. The “Old” one is a mix though. Colt slide from 1912 and a Lone Star Armaments frame. She shoots GREAT. The newer series 80 looks very modern but i have had some feed issues… I love my AR’s, i have built 4 for myself, i quit buyin and started assembling. It is FUN! I have 4 super reliable awesome looking AR’s. 20″,18″, 16″ and of COURSE, a 10 1/2 in pistol which is a baaad lil serpent… So i love the AR platform, but i think Colt just drew a bad hand and i am awaiting their ressurection… Hopefully. Love the 1911’s, revolvers AND AR’s. I compete a lil with mine and plink and hunt and are the gun closest by! Always a AK too, sorry gotta say it,.love the kalash !!!OUT, Lates!

  19. The main adversary of the British in South Africa
    Was the Boers, or Dutch settlers. The reference to the Zulus as adversary is
    likely made with Rorke’s Drift, Battle of, in mind; and memorialized in the 1965 film “Zulu.” The British were armed with Martini Henry breech loading, single shot
    rifles, not Lee Enfield bolt action, mag fed rifles.

Your email address will not be published. Required fields are marked *

Your discussions, feedback and comments are welcome here as long as they are relevant and insightful. Please be respectful of others. We reserve the right to edit as appropriate, delete profane, harassing, abusive and spam comments or posts, and block repeat offenders. All comments are held for moderation and will appear after approval.