We’ve gone over AR-15s and AR-10s a lot here, but what we’ve never done is compare the two.
These rifles are integral not only to firearms and military history, but also to each other’s development, and the story behind them is one of the most interesting parts of firearms development in the Western world.
Hopefully, if you’re trying to decide which one you want, or just want to know what the difference is between the two, this will help.
What exactly is the difference between the AR-10 and the AR-15?
Why would you choose one over the other?
I’m so very glad you asked. Let’s get started.
Table of Contents
The Birth of the AR-10
Early in the 1950’s, the Fairchild Aircraft company began work on designing what would go on to become the first of the “AR” line of rifles, the AR-1. Called the “Para-Sniper,” this rifle was designed as an upgraded paratrooper weapon and was meant to be light, relatively short, and easy to jump out of a perfectly good airplane with. 25 were produced.
Shortly thereafter, the company created a subdivision that would go on to become known as Armalite. Armalite, being far too small and underfunded to become a major player in the arms manufacturing world, was instead focused on prototyping advancements to existing weapons platforms that could then be sold as designs to large manufacturers.
Months later, George Sullivan, the founder of the Armalite company, was testing a version of the follow-up to the AR-1, the AR-5 survival rifle, which was meant to be used in survival situations by airmen who had been shot down, particularly in remote locations or behind enemy lines. This rifle would go on to become the popular AR-7 survival rifle still made today.
Prices accurate at time of writing
Prices accurate at time of writing
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While at the local range for the testing, he met Eugene Stoner, a small arms designer and the rest, as they say, is history.
Stoner would go on to serve as Armalite’s chief engineer and during his tenure would develop the rifle we now know as the AR-10, as well as the AR-15/M16 later on.
The 7.62x51mm AR-10 he developed first was submitted to the US government as a replacement for the M1 Garand, but ultimately lost out to the Springfield Armory M44E4, the rifle that would go on to become the M14.
Despite this setback, Stoner and Armalite continued to refine the AR-10 concept, including replacing the aluminum/steel composite barrel (a George Sullivan addition that Stoner strongly opposed) that failed dramatically during torture tests and killed the rifle’s chances at early adoption.
The Birth of the AR-15
Following the relative failure of the AR-10, Eugene Stoner and other engineers including Jim Sullivan decided they weren’t through yet, and began work on a smaller .223-caliber rifle to submit to the CONARC (U.S. Continental Army Command) testing meant to replace the Browning Automatic Rifle, M1 Garand, M1 Carbine, Thompson Submachine Gun, and M3 “Grease Gun” all with a single rifle.
Despite performing well in an admittedly very difficult challenge, Armalite’s submission, the .223-chambered AR-15 was vetoed by Army Chief of Staff General Maxwell Taylor in favor of the M14. This was despite the AR-15 proving to be three times more reliable than the M14 and one AR being worth two of the larger rifles in terms of firepower and carriable ammunition.
Frustrated with this setback and dealing with some major funding issues, Armalite closed the doors on it’s machine shop and sold the designs of the two weapons to Colt, who then immediately moved the charging handle of the AR-15 back to the end of the receiver as it was on the original AR-10, and geared up to mass produce the rifle in large numbers, something that would prove key to the success of the rifle later.
Eventually, after some success in smaller markets, General Curtis LeMay, Vice Chief of Staff of the Air Force at the time, ordered a number of AR-15’s primarily for pilots to have a fighting chance if shot down, echoing the AR-1’s original design intention.
In 1961, LeMay was promoted to Chief of Staff of the Air Force, and requested an additional 80,000 AR-15’s to arm his personnel with, finding the lighter and lighter-recoiling smaller-caliber rifle to be much preferable and effective to the larger M14 in service at the time.
Meanwhile, the Army’s continued testing of the AR-15 found that the .223/5.56 rifle was much easier to shoot (especially in full-auto) than the 7.62mm M14. That same year, the Army found that 43% of shooters with the AR-15 qualified Expert in marksmanship trials compared to 22% shooting expert with the M14.
Despite all of this, and seemingly determined to be on the wrong side of history on the issue, General Maxwell Taylor, now Chair of the Joint Chiefs of Staff, again vetoed the AR-15, claiming that having two differently-chambered rifles in service at the same time would be problematic.
Taylor and LeMay would continue to clash over the issue, especially when it became evident that the AK-47 was vastly out-performing the M14 in the early days of the Vietnam War.
However, after the M14’s production was halted due to an inability to meet demand, LeMay finally got his way after it was decided that only the AR-15 could be produced in significant quantity to arm all branches of the military for the rapidly intensifying conflict in Vietnam at the time.
Colt’s heavy backing of the platform and massive manufacturing output capabilities would thus save the rifle, and change the course of history forever as intermediate-cartridge rifles that allowed troops to carry hundreds of rounds of ammunition easily would become the norm, and in the case of the AR-15 itself, would birth a rifle to rival the popularity of the still-ubiquitous AK-47.
Following some minor tweaks, including the addition of a forward-assist that the United States Airforce, legendary weapons designer Eugene Stoner, and your humble gun scribe here all find to be a useless expense, the rifles Colt produced to meet the needs of the military would go on to become the M16 which, despite some early issues, would go on to clash with Kalashnikov’s best work not only on the battlefield, but in overall popularity as the design of choice for military rifles the world over.
You can check out the full history of the M16 for more information.
Modern AR-10s, whether produced as “Armalite-style” or the latter “DPMS-style”, are all really just scaled up versions of the AR-15’s that were produced by Colt. These rifles are still commonly used on the battlefield today, but they are also massively popular in the civilian market (in America at least) in semi-automatic variants.
Unlike the original design, which was only chambered in 7.62×51, modern AR-10’s come in a variety of “long-action” chamberings including the increasingly popular 6.5 Creedmoor.
These AR-10s see use many places today, particularly by long-range shooters, whether they are hunting enemies on the battlefield, wild game, or just a higher score at the range.
Be sure to read about the best of the modern AR-10s if you want to know more about how the rifle has evolved.
Modern AR-15s are made by…just about everyone with a machine shop, it seems like. Despite new advancements such as piston-driven gas systems to replace the original direct-impingement system, the design has remained mostly unchanged this whole time. You can see the full list of internal AR-15 parts for more information.
What has changed, is the calibers on offer. Much like the AR-10, the AR-15 is available in a wide variety of chamberings from the original 5.56mm/.223, to modern chamberings like the 300 Blackout and 6.5 Grendel special-purpose cartridges.
Note: Be sure to check out our look at the exciting new .224 Valkyrie cartridge.
Why Choose an AR-10?
So, if the US military picked the intermediate chambering of the AR-15 over the big 7.62x51mm chambering of the M14, wouldn’t it follow that it would be better to choose an AR-15 than the AR-10?
If you’re looking to get the best accuracy and power at long distances, or just need a lot of stopping power in general, the AR-10 may be your best bet.
Sure, there are options for the AR-15 that are purpose-built to do more damage at range or stay super-sonic longer for better accuracy, but these options are often chosen because the rifle they are fired from happens to be lighter, cheaper, and more supported by the firearms industry.
If you truly need the extra power and accuracy at the range or need something that’s going to impart the maximum amount of force to a target at any range, the AR-10 may be the better choice.
Personally, I like the AR-10 better for those long shots, or if I’m hunting dangerous game up close. I’ve talked before about my noted dislike of wild hogs. My hog-hunting guns are a lever-action in .45-70 and an AR-10 in 7.62. I’ve never doubted that either will stop a charging 250lb boar with a single shot, provided I do my part.
Not that I especially enjoy having to make that particular shot. But I have made it on two occasions, both with the AR-10. I also missed it on one occasion that ended up being a very close encounter.
In that scenario, I was incredibly glad for the rifle’s fast follow-up shot potential. There’s a reason lots of SF folks choose 7.62mm battle rifles for when every shot counts in a close-range situation.
My precision long range gun is also an AR-10, and while it’s not as accurate as some of the finely-tuned bolt guns out there, it’s also not nearly as expensive.
I’ve also accepted 1st place prizes when competing against some of those bolt guns, which just goes to show that, in the right hands, the AR-10 can still run with the big boys when it comes to accuracy.
Why Choose an AR-15?
Not everybody needs that extra range or stopping power though (or the extra expense). If you’re looking for a good rifle that can still hit what you point it at, and do it over and over again without breaking the bank, the AR-15 is an excellent choice.
It’s still a lighter-recoiling, easier to shoot, cheaper to shoot rifle that is, right now, being used on battlefields across the world in one select-fire variant or another.
The AR-15 is also (arguably) the most popular gun platform in the world, and if it isn’t, it’s second only to the AK-pattern rifles that came to market a little earlier and therefore had an unfair head start.
What does that matter? Well, go to any gun store or even your local Walmart and you’ll find ammo for your gun. You’ll also, depending on the current political climate, find parts, magazines, accessories, and other copies of the rifle itself.
That level of aftermarket support also means you can do just about anything with your rifle, from hunting to building a recce rifle to home defense. And you can reconfigure your gun on the fly, with minimal tools or gunsmithing experience.
This makes the rifle a great purchase for shooters who need one gun to do it all, which is something the AR-15 really excels at, especially once you realize you have access to a wide variety of calibers and cartridges just by swapping out the upper assembly.
It’s also easy to build either of these rifles, but it’s a lot cheaper to build an AR-15 provided you have the right tools on hand.
Or, do what I did, and get both. Both rifle styles are absolutely amazing if used for their intended purposes, and neither will disappoint. I’d say if you can only get one, go with the AR-15 because it’s easier to shoot and cheaper to feed and maintain. If you want one to hunt with or make shots past 800 meters, go with the larger-caliber AR-10.
If you have the money, get both. You won’t regret it.
Here are our Buyer’s Guides for both the AR-15 and the AR-10.
What do you think of the AR-10 and the AR-15? Do you own one or are you thinking about pulling the trigger (pun intended) on a purchase? Let me know in the comments below.
27 Leave a Reply
Matt, thanks for posting. As a beginner, this was useful. I'm looking for home defense both inside and outside. The AR-10 is so far my choice for outside the home (remember the McCloskeys?). I wouldn't trust myself indoors with it and have other guns for that.
As a Texan who's suffered yard damage from hogs, I very much share your dislike of them! I'd love to see any videos you or anyone has taking down hogs with your AR10! They're an abomination and need to be culled aggressively. Why haven't we turned them into dog/cat food or even free exports ??!!
Famine is killing kids in Africa right? Well, we got hog meat! Someone ought to start a non-profit for that. Some of us would donate $$ (meat processing etc....) Others would donate a 308 with a dead sow at the end =)
In 1974 ND 1975 my Marines in G Company , 2nd Bn, 3rd Marines carried M-16s in 1974. Everyone knew it was a modern infantry rifle designed for maximum lethality against large numbers of enemy combatants on the battlefield. It's not a "sport" rifle. It's a weapon of war designed for killing human beings quickly and violently.
America has the worst per capita gun rate in the world. But there are virtually ZERO gun violence events on US military bases. Why ? Weapons are under lock and key when not in use. Ammo is stored under armed guard separate from firearms. Users are trained in safety, correct use of firearms. All weapons are tracked and accounted for by serial #. And by the way, my Sig Sauer Ar 10 is a heavy P.I.G. suitable for the battlefield and the expenditure of large amounts of ammo.
Putting 20 million of AR style weapons in the hands of the largely untrained, unregistered and clearly unsafe American population for the sake of gun profits, while promoting violent insurrection against our nations government and elected leaders along with misinformation pro gun violence propaganda is disgusting, gutless, profit seeking, right wing seditious idiocy. Pew Pew ? An appropriate name for those seeking to make believe these weapons aren't deadly weapons of war. Anti gun safety extremism is destructive, stupid and a threat to all Americans.
haha ar-10 go pew pew pew
Now were blaming gun manufacturers for promoting some kind of insurrection? Nonsense to it's limit. 1/6/21 was NOT an insurrection, but liberal politicians and media keep trying to sell it for political advantage. Tell me exactly WHO visiting the Capital that day actually discharged a firearm? I know of only one: Lt. Michael Byrd in the tragic murder of Ashli Babbit, which has gone unpunished. If there were ANY other gunshots, we would still be hearing about it 24/7.
Oh shut up. And while you're at it bring that same energy for aborted babies. If you think an AR 15 or M16 is destructive wait until Jesus returns on Judgement Day.
The origin of weaponry goes much farther than the gun.
The first being with a weapon in the Bible wasn't even humans, it was the cherubim with that technologically advanced sword in Eden.
Enjoyed the article. I have rhe AR both calibers and Enjoy shooting both. Unfortunately due to the cost and shortage ammo, the shooting enjoyment is limited.
I originally purchased the AR-10 for hunting mule deer but never got around to setting it up for that. Hopefully I'll get around to getting it cherry for the hunt.
Thanks for the article!
I have both. I love the AR 15 never had problems with it. It shoots more accurately than my old eyes can. I could love my AR 10 except for a major problem I have been unable to solve. Failure to eject. Being going on since the start. I've changed ammo, magazines and BCGs. Sent the upper back to CMMG and they tested it out and said it is OK. I like the rifle so, I am going to solve this eventually.
Change the spring
Ok, I will try that. Thanks for the tip.
So I would just like to clear this up. If someone is talking about they have an AR15 chambered in 7.62 they actually have an AR-10. Is this correct or are there 15s that shoot 7.62
Naw - they mean they have an AR-15 that shoots 7.62x39. It’s never been an upper I’ve personally wanted but guess if someone owns several AKs it would make sense. But that’s what someone is referring to with a 7.62 AR-15.
Just purchased (MY FIRST AR-15) DPMS AP4 Carbine and ordered quite a few mods and a scope for it (although Scope and "ALL" the Mods arrived and still waiting on back ordered Rifle. I am also going to be looking at building and AR-10 if you could provide some advice?
I am new to building any AR platforms. I was wondering if there is a buyer's guide for tools needed to build AR's?
"hey honey, are you going to the walmart? please dont forget some milk.... and bring a few boxes of 308 win.. we are almost run out. And some bmg.50 for grandpa... kiss!
I keep on admiring you Americans
I just recently built my 7.62x39 AR 15 and this is by far my favorite rifle.. I can shoot it all day at the range and never have a sore shoulder.. With my red dit laser sight and 3x magnifier its accurate at 400 yards which mskes it perfect for hunting deer or hogs and home defense.. I'm getting a .223 upper so I can quick change for small game.. This gun ROCKS ! ! ! If you can only have one rifle the AR 15 is the way to go and the 7.62x39 ammo is ridiculously affordable..
I can stop a hog with one shot with NATO 5.56.
I have recently built a AR 15 pistol with a 10.5" barrel. I chose a 7.62x39 caliber because the 0.223 cartridge loses too much power using a short barrel. In addition, there is a lot of cheap ammunition out there albeit steel. So far, I have shot about 60 test rounds and it is working well. I have decided to set the rifle up with a brace (Gear works Tail hook Mod 4) and red dot scope (Burris Fast fire 3 8 MOA). These parts should arrive shortly.
ANYONE KNOW IF THE UK'S BRILLIANT ADOPTION OF THE LMT MWS CQC VARIANT WITH THE "RUMORED ISR UPPER (LIKE THE CSW "ROOM BROOM" 300 BLK VERSION OUT NOW FOR SOCOM UNITS) IS BEING USED BY ANY OF OUR GUYS DOWNRANGE? THE FEW SOF OLD SALTS I KNOW SWEAR BY LARUE OBR/KAC SR-25K2s in a customized ISR STYLE SETUP IN A 14.5" CONFIG, BUT WHAT ABOUT THE REPR ii (I DON'T CARE IF IT LOST TO THE SAME REBOOT OF THE 417 FROM THE HK GIANTS, AND NEITHER DO THEY) OR THE WILSON COMBAT RECON TACTICAL IN 14.5"???
THEY EVEN HAVE US ARMY ARDEC WORKING ON LMT MWS 7.62s of these guys!!
I'd like to know what guys are RIGHT NOW (outside of the MK 17 SCARs) bringing to the fight in our US SOF untis, especially the SMU types in JSOC.
I have the AR-15 rifle but I am sitting on an AR-10 lower contemplating whether or not to build it for that extra long range target shooting
I have both and really enjoy them. good article.
Both... I bought 308 Dpms Sportical... decided on upgrades, free-float, special trigger, pistol grip...Florida and big hogs
I like to stick to NATO and cheap ammo for range and hogs...also fun ringing steel at 100yds... I load my own competition ammo.
223 will turn into 224 valk soon...will keep 223 upper for economy shooting
I enjoyed this article, was informative and fun to read. I do agree with the points made by the author - AR-15 for an introduction to shooting or for the smaller statured people or those whom are a bit nervous of recoil and even younger people. The AR-15 is bar far the most enjoyable modern rifle to shoot especially for those new to the hobby/sport. The AR-10 has it's place too and the recoil can be tamed a bit more with the proper muzzle device and upgraded buffer w/ spring. I am currently building my AR-10 now (yes 7.62 NATO) with Aero Precision's upper & lower combo. I have 75% of the parts = just holding back until I can get a nice handguard, buttstock and trigger (installed a basic milspec for now). I plan on using the Armalite 20" barrel (fluted) with it and start learning how to shoot @ 1000 yards ++. I think it's time I took my skills to the next level..... too bad my wallet won't let me do what I REALLY want to do with it (and grow my collection too (: )
**Side note: Just recently came across this site and I am very happy I did. Lots of awesome resources and info here. Looking forward to what's coming from the Pew Pew Tactical Team!**
"I prefer DANGEROUS FREEDOM over PEACEFUL SLAVERY"
Glad we could help out and let us know how your AR-10 build performs!
Excellent article, as always! To the best of my knowledge, Armalite submitted the original AR-10 to the Army trials late in the cycle. When the AR-10 started showing issues in those trials, there simply wasn't enough time left for them to correct them before the trials ended and the Army chose the M-14. Its interesting to think about this. Had Armalite succeeded in the initial trials and the AR-10 was chosen over the M-14, they wouldn't have had the financial reasons to sell the designs to Colt and may not have had reason to scale down the design to the .223/5.56 caliber AR-15 we all know and love today..
This is a good point! One of the main issues the AR-10 had early on is that, unlike the T44 and FN FAL that were the two other contenders, it was still a prototype, not a finished rifle that had been extensively field tested.