With AR-15s it seems you can pretty much build whatever you want.
From super lightweight PDWs with 11.5 inch barrels and collapsing stocks to 24 inch equipped Special purpose rifles with carbon fiber barrels. If you dream it you can build it.
Of course, just like car enthusiasts have a tendency to be most excited about building classic cars, a lot of firearm enthusiasts want to build classic AR-15s. One of the most prolific classic AR-15 models is the M16A2.
The M16A2 holds a special place in my heart because it was the rifle I carried through boot camp, and I was in one of the last boot camp cycles to issue the A2 to recruits. The M16A2 was a Marine Corps led project to improve the M16 after its Vietnam experience.
It served from the mid-80s well into the War on Terror. It can still be found in reserve units and marksmanship units. It’s also a common sight in the service rifle division at NRA High Power matches.
Today we are going to look at what it takes to build an M16A2 replica, an AR15A2 if you will. I’ve seen a lot of people asking about it, so I’ve assembled a list of the parts you need to build an M16A2.
Couple it with our How to Build an AR-15 Upper and How to Build an AR-15 Lower and you’re set!
Or if everything seems a little too difficult…Stag Arms has got you covered!
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The Unique Upper
What really sets the M16A2 apart from modern AR 15s is the carry handle equipped upper receiver. This carry handle upper receiver gives the M16A2 a very unique profile, and makes it stand out in a world of flat top uppers.
This can be one of the harder parts to find, especially if you really want that classically fixed carry handle instead of a flat top with a mounted carry handle.
Oddly enough I’ve never seen someone actually carry the gun by this handle. Personally, I know the idea of using the carry handle to carry the rifle would have resulted in ‘corrective action’ in boot camp.
The entire carry handle concept is odd, and I think that’s what makes the retro M16s so unique.
Luckily, we have two options. One’s the classic choice, while the other is a more affordable option for those on a budget.
For a more authentic M26A2 clone, I suggest the Colt A2 upper receiver. This is as close to the actual military upper you are going to get your hands on.
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If you’re looking for something a bit less expensive, DPMS makes a very affordable and noteworthy model that’s true to the standard A2 design.
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The M16A2 upper is equipped with a robust rear iron sight with two apertures and tons of adjustment potential. The above uppers are both stripped, so you’ll need to purchase the rear sight separately.
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You’ll also need a standard upper parts kit to finish your rifle, including the dust cover and forward assist with the necessary springs and pins. Aero Precision makes excellent guns and gear, and this kit is a bargain.
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The Barrel and Beyond
A 20 inch barrel on an AR makes the gun sound like a beast in a world of carbines, SBRs, and AR pistols. The 223/5.56 round was designed for use with a 20-inch barrel so you’ll be getting optimum performance.
20 inch barrels are easy to find, but I suggest Faxon because I know they are high quality. A barrel typically isn’t something to skimp on.
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Once you’ve got a plain barrel you’ll need a few more things to make it an A2 barrel. First, you need that fixed front sight. Daniel Defense not only makes one but makes one of the most affordable models.
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Alternatively, if you want something a little simpler you can get a 20-inch barrel with a fixed sight base already attached by Brownells’s own brand of premium barrels.
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Regardless of what route you go, you’ll also need a gas tube and A2 flash suppressor. The rifle length gas tube is actually a major advantage of the 20-inch barrels. You get less recoil, and the gun runs cooler.
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The A2 flash suppressor is one of the best flash suppressors out there and acts as a compensator as well, plus they’re common and cheap.
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You’ll also need those famous polymer round handguards. Rail systems on rifles were only a dream when the M16A2 entered service and rifles were kept nice and light using polymer handguards. Rock River Arms makes an excellent set of classic round handguards that use triangular caps.
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You’ll also need a few other miscellaneous small parts:
- Handguard Liners
- Delta Ring Kit
- Barrel Nut
- Barrel Indexing Pin
The Rifle’s Heart and Soul
At the core of the rifle, resting comfortably and softly in the upper receiver is the bolt carrier group. The bolt carrier group is easily one of the most important parts of the rifle, and you have literally tons of options. If you want more specific info, check out our article on BCGs here.
However, if we are being legit with our A2 build we gotta go with the classic M16 full auto BCG, with a mil-spec phosphate coating. You have tons and tons of options, so the real question is which one do you want?
Personally, if I’m going legit A2 I’m going with a Colt BCG.
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It’s a little pricey, I know, but there are less expensive alternatives. Brownells, for example, makes a very simple and very affordable option.
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The Complete Upper
If you appreciate things nice and simple, don’t have a ton of time, or are just a little lazy you can also go with a complete upper option, with the right upper, barrel, gas tube, bcg, etc. included.
This one is from Anderson, who famously makes some of the most affordable, but still quality, lower receivers.
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Gettin’ Low
That’ll about do it on our upper receiver so now we can focus on the lower half of your A2 build. The good news is choosing a lower receiver is pretty easy to do. Unlike an upper, you can basically use any standard mil-spec lower receiver.
The standard AR 15 lower receiver hasn’t changed since the A2 so you can throw a dart at the Brownells catalog and pick whichever receiver it lands on. Personally, I’m a fan of Spike’s lowers. They are well priced, easy to find, and high quality.
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However, any forged 7075 T6 aluminum lower with an anodized finish will be technically correct. Stay away from lowers with short throw safeties, and stay far away from polymer if you want a legit M16A2.
You’ll also need to put the clothes on (or in I guess) that stripped lower. For this, you again have dozens of choices. If we are keeping it legit you can go with the Colt Lower parts kit.
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This kit does not include the pistol grip or trigger. Both are easy enough to find.
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If you are looking to build an A2 for service rifle competition, then the Rock Island Match trigger is a great option for you. The Rock River Arms Match trigger provides a clean and crisp pull that comes in at about 4.5 to 5 pounds. It’s a two-stage trigger that is much cleaner and smoother than any mil-spec trigger.
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For those who want to go the simple route, there is are complete lower kits that are both affordable and easy to find. Bushmaster has a great classic mil-spec option that’ll fit in an A2 build.
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And for competitors that want to make their build easier, Rock River Arms also has a complete lower kit that includes their Match Trigger.
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If you want to make your build as simple as possible, there are always complete lowers with an installed lower parts kit. This will save you a bit of time, and likely some frustration from that irritating front pivot pin.
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Stocked Up
Finally, we get to the rear of our A2 build. The A2 again has what some would consider an antiquated stock. It’s fixed!
Oh, the humanity! It doesn’t collapse, fold, and it’s not easily removable. However, it is quite durable, provides an excellent cheek rest, and even has a compartment to stow things in.
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Few companies make authentic A2 stocks, but High Standard is one of them. The High Standard stock is completely mil-spec, down to the aggressive triangular texturing on the end of the stock.
You’ll also need a rifle buffer, rifle buffer spring, and rifle buffer spring tube. All are somewhat odd in the days or carbines and collapsible stocks. Luckily, Brownells piled everything together in one kit, making this much easier.
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Finishing Touches
Of course, you are going to need some mags to make the whole thing run right? Well if it’s an A2 clone you can tell those Lancers, Pmags, and Hexmags they gotta go. No for an A2 build you gotta go old school aluminum.
The Brownells brand aluminum mags are mil-spec, cheap, and available in multiple quantities.
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For those poor souls in states with capacity limits, Brownells has ten rounders available as well.
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Extras
Now the following items aren’t needed for an M16A2 clone, but they can add a little pizazz to your build. These accessories hark back to those easier days, where rails weren’t a thing, and our version of MLOK was duct tape.
Bayonets
Bayonets are actually still issued with the M16A4 and the M4 rifles. Bayonets have been part of the military’s inventory for hundreds of years, and will likely remain so, but do you really need one?
Probably not, but a bayonet definitely adds something extra to the build. As much as I love things that go boom, I also like pointy things. I’m tossing two bayos up here because the M16A2 served long enough to be issued both.
Ontario M9 Bayonet
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The M9 bayonet is the bayonet of the United States Army. It doubles as a combat or general utility knife. A bayonet has to be extremely well made for it to function correctly. Good thing this bayonet is designed to be used as a spear point.
Ontario was one of the many companies who was contracted to produce the M9 bayonet and they still manufacture the design. If you’re buying a bayonet you might as well buy one from a company who makes it right.
Ontario OKC3S Bayonet
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This is the bayonet I know and love from my time with the Marines. The OKC3S is essentially the famous Marine Corps KA-BAR turned into a bayonet. It features a 7-inch blade with a little serration at the end. The OKC3S is issued to almost every Marine carrying a rifle and they were even used in Fallujah.
Marines still train with bayonets and are required to prove proficiency to obtain their tan belt and graduate boot camp.
Barska 4×20 Electro Sight
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This replica of the classic Colt scope proves you can toss an optic on an A2 without issue. Barska produces an affordable Colt replica that gives the user a 4 power magnification, and a sleek old school look. The Barska sight isn’t a go to war optic, but it’s perfect for capturing that old school cool look and feel of the A2 platform.
GI Sling
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In a day where elaborate slings rule the roost, the classic GI sling feels a bit underwhelming, but this style of sling has served for decades! It’s simple, reliable, and the M16A2 platform works perfectly with it. It’s another complete the look accessory.
That’ll Do For an A2
M16A2 builds, and retro builds in general, are a very popular trend in the AR world. Brownells is even selling old school AR receivers and furniture for A1s. Just a quick glance at R/guns reveals how popular retro builds are.
Plus you can get a full retro kit from Stag Arms.
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It’s odd to see so many people clamoring for carry handle equipped uppers, but I guess everything is cyclical.
If you need a more modern AR-15, you’ll want to read our Complete AR-15 Buyer’s Guide!
Readers, do you guys and gals have an interest in retro ARs? What about retro guns in general? Let us know in the comments!
26 Leave a Reply
PSA has m16a2 marked lowers.
The carry handle worked on our A1s because it was in balance and carried level. perfect for bailing out of a M113
Man, I'm glad that trained with the a2 as well, shipped out to boot camp Dec of 09.
This is a great reference. And a terrible enabler.
Can you recommend an M16 A2 upper with carry handle that is compatible with a PSA lower receiver?
I love all the "how to" guides. I'm trying my build my first A2. Brownells no longer has the high standard stock and I couldn't find it elsewhere. I've checked out a few others but all the ones I read about all had some reviews of feeling cheap. PSA had mostly good comments but the two most recent reviews noted that the quality seemed to have dropped off recently. UTG was consistently panned as cheap. Anderson's kit also had some "cheap feeling" comments.
Any suggestions on where to find a quality stock and buffer tube assembly? I'm not opposed to buying a complete lower kit. A polished trigger would be nice too.
The Colt M16A2 I was issued in BcTC had a plastic stock that can only be described as brittle and cheap. I was amazed at the fact that the simple majority managed to not be destroyed at the bayonet range. It’s the buttstroke that’s fatal for those cheap, unsturdy old plastic stocks. Maybe they were better in the 70’s but by 2006 they were cheap and brittle. Recoil on an M16 length rifle is extremely negligible, to the point my first shot I raised my leg and cleared my m16a2 and told my Drill Sgt I had a pop and no kick. He laughed as he yelled at me “it ain’t your daddy’s deer rifle!”
When will you guys be doing an A4 clone build?
M16A4 build is actually on our calendar right now and is coming up very soon...I would highly recommend checking back next week!
Right here! https://www.pewpewtactical.com/best-ar15-builds-m16a4/
I enjoyed this article as I prefer old school weapons.
I joined the Corps in 84 and carried the A2 when I wasn’t lugging around an M60 (wish I could afford one of those). A few years ago I lucked upon a Colt Ar-15A2 in a Virginia gun shop. It was made during the Clinton gun ban years so it has the detachable carry handle, the front sight assembly doesn’t have the bayonet lug, and no flash suppressor. It is a match grade model with the heavy barrel, that retailed for close to 2 grand new. This is where I got lucky. An employee of the shop had bought it new and carried it home, stuck it in the safe and forgot about it. He never fired it. Decided he no longer wanted it so he carried it in to work and stuck it on the shelf as a used rifle. I got it for $1000. I am fixing to go retro on it and have the barrel threaded for the flash suppressor, and replace the front sight assembly. The most expensive part is going to find a new Colt A2 upper receiver with the attached handle. I want to stay true Colt and not use other manufacturer parts.
SEMPER FI!!!
Fulton Armory looks like they have a pretty solid A2 clone (highlights are the govt profile chrome lined barrel IMHO). Anyway, I feel the same way about the A2, went through all my training with it and miss it, especially when I consider my deployment M4 came when those front heavy "rail cover carriers"...
Barely anything in this article had anything to do with building an actual A2 clone. Incorrect complete firearms, incorrect uppers, incorrect bayonets, incorrect lowers (for a true clone.)
why did you show an A1 and then the wrong bayonet jar head? Bite the bullet.
The first time I saw a M16A1 was at Randolph AFB in Texas (summer 1970) where we went through combat training for my 1st tour in Nam (actually out of Thailand) in our UH-1F Gun Ships after being activated from the USAF Reserves at Scott AFB ILL, where we almost never shot a rifle (as pilots) and when we did they were with M14's. I've hunted since a kid, so I loved the M-14. While we did have some UH-1 time in the Reserves, nearly all my3 years in the Reserves was flying CH-34 Choctaw's as part of the 27th Airlift Wing. I grew up in a huge family farm in N Illinois and had been flying , since I was 14 one of three Stearman we had as converted crop-dusters and a couple Korean War surplus Bell H-13's my uncles bought for the duster business on smaller fields. I was transferred to the 20th SOS (Spl Ops Squadron), which were all UH-1 Gunships and AT-28 Trojans setup for ground attack/support; by early '71 we got new AH-1F's Cobra's. Since we were always in hostile zones we were also issued M-16A1 along with an 1911A1's and had to learn how to use the M-16 if we went down. In clean conditions the M16A1 was OK, but in dirty inclement conditions (where in SE Asia isn't it?) there were problems. It was very routine for Helo flight crews to turn, leave behind or throw away their issues A1's and instead use Winchester "trench" shotguns, beg-borrowed-stolen M-14's from field warehouses, or most often captured AK-47's with a case of 7.62 ammo in each bird. I have to say that I've had a very bad taste in my mouth for anything from the AR-15/M16 family. Instead I bought a gorgeous new FN./FNC w/folding stock in 5.56 NATO some 25 years ago and love it. BUT I had the chance a few years ago to pick up a sweet barely used Colt M4 carbine so cheap I couldn't say no and I like it nearly as well as my FN/FNC. I really wish the M4 Carbine versions had been around in 1970 for flight crews, I would have savored it over the AK-47 for sure ..... BUT, I still believe the M-14 was the best "Service Rifle" (not close quarters carbine) the Military has ever had - Best Reliability, Best "Knock Down" power and Best Reliability, bar none.
I joined 2/8 Mar the week it became the first line unit to be issued and deploy with the M16A2. I had spent the past two years on Barracks Duty where the only time we even saw our service rifles was to clean them for IG inspections as we carried 1911s and 870s on duty. I fell in love with the A2 the first time I picked it up. Despite a broken sear at the 300yd line that transformed my "well-aimed 10rd slow-fire" into three 3rd bursts and a prayer, I came off the range having not fired a service rifle for over two years with a 238/250. Yes growing up shooting in WV was a factor but that gun literally wrote my ticket for the rest of my career.
A bit of clarification on the carry handle. It was the guard over the top mounted charging handle on the original design. A few changes were made including moving the charging handle to the rear oF the receiver. Rather than redesign the entire rifle, the upper and front sights were left as is, thus giving it the appearance of having a carry handle.
Great article.
I didn’t see a mention of a retro styled charging handle (I may have missed it) - I know standard charging handles are all pretty much the same but any links or advice on a period correct looking one?
I carried an A2 in the Army (2003 - 2009), and hated it. It was the dinosaur passed to the aviation units once the BCTs transitioned to the M4, since Army brass decided (rightly) that we were highly unlikely to engage in direct combat. Having to carry that broomstick in very tight, confined, and sensitive places (try working underneath/inside your car everyday while having to lug around an A2, and you'll soon see the folly) was worse than useless; we didn't have any ammo on-hand anyway, so carrying the weapon was just a nuisance - "check the block" security theatre. An M9 in a shoulder or drop-leg holster was a better service weapon in that application.
One thing I did note in the article is that the Colt stripped upper is actually the A2 upper, whereas the DPMS upper looks like an A1. That certainly will not fit the A2 rear sight aperture.
Kudos to those who appreciate the old school style!
i was 11-b and loved my FN A2. my M4 was a piece of shit. thanks for your support role pog.
The dpms a2 Upper pictured is an A1, note the rear sight. Decent article but with a little research the builds can be completed cheaper and better detailed.
Monte,
Thanks for the head up. I link to pics rather than upload and for some reason the link picture changed. If you click it it takes you to the A2 upper. Not sure what happened there.
Eric, I guess I’m kind of old school (early action in Nam (65-68) and don’t like the pretty AR15. Going on the low-end, what is the bottom line on a complete build for the M16A2? I will not be shooting a lot of ammo down range.
Thanks for the info Travis, Ive been wanting to build retro A 2 for awhile now and your article just stirred that interest back up after seeing the colt a2 upper at Brownells I think I will be ordering it right after making my comments
What do you think the total cost of a cheaply built one would be?
For cheap, you can go to Palmetto State Armory and they have an A2 build kit on sale right now for $450 shipped. Just add a lower and you can build an A2 clone for around $500. Price is good until Monday @ noon ET (or until they sell out).