Marine Corps Colt IAR M27 Submission – Rare Colt Rifle

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Colt submitted a rifle to the M27 IAR trials. The Colt IAR M27 submission had a unique heat sink and could significantly increase the number of rounds the rifle could fire. Colt sold these uppers for a short time to civilians before shutting down production.

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Marines use M27 as Infantry Rifle:

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  • Country Boy Guns

    Rest in peace, Cory.

  • Tim Allen

    With this video being the only information I have on the rifles I think the Colt seems to be the better option.

    My condolences for the loss of your friend Cory. May he rest in peace.

  • Chase Ferguson

    Hate to hear that. I’m glad we have all been able to have a community around the second amendment and enjoy good men and women in the process though. Prayers for his family.

  • Mrgunsngear Channel

    Great info. Random nugget: Some of the Colt IAR submissions had FDE anodized buffer tubes and FDE Vltor stocks and some were black. No idea why.

  • Freedom and Bacon Homestead

    I’m sorry for your loss. RIP, Cory.

  • TJ Murphy

    The magazine in the minimi was never reliable, they should have bought the Israeli ng5 machine gun which also has a semi auto option and can also take magazines as well as a belt

  • Joshua Villegas

    Firing the M249 SAW in semi-automatic is a sin of itself!

    • Military Arms Channel

      Welcome to America, land of the mostly free but not really.

    • tongo382

      No one can afford a pre ban full auto.

    • 100radsbar

      @Military Arms Channel At least you can own one, not here in Denmark. Semi-auto rifles need to be equivalent to around .308, or higher, and we have a magazine capacity of 10 rounds maximum for semi-auto rifles. The minimum legal caliber for semi-auto rifles is a bullet weight of 139grains, with an impact of 2700 Joule at 100 meters, or a bullet weight of 154 grains, with a bullet impact of 2000 Joule at 100m meters. This rules out many calibers, especially .223, .300 Blackout, etc. But on the upside, they have now removed the need to register for for owning a suppressor for your rifle. If you have a permit for a rifle, in say .308, you can freely buy a suppressor for .308 over the counter. You just have to show them a valid hunting license, and a permit for the rifle, no registration required.

    • timewave02012

      @100radsbar People can argue all they want about balancing the merits of guns for self defense with the harm to society caused by criminal misuse, but when there’s no general consensus on what should and shouldn’t be restricted (suppressors are heavily restricted in the US), that tells me the restrictions are not founded in logic.

    • Socrates Socratous

      @100radsbar Awesome!!! in Cyprus we are aloud only 12 gauge break action shotguns with 2 rounds max capacity. even airsoft is illegal…

  • 64samsky

    So sorry for the loss of your friend Corey, may he now rest gently in God’s arms.

  • KamikazeK P09

    I think maybe there’s one big thing that’s being overlooked with the Colt MAC….direct impingement gas tube. Sure it can be beefed up somewhat, we all know that’s the intended weak point of the AR operating system, the sacrificial part that saves the integrity of more expensive/difficult parts to replace.

    With the intended increase of sustained rates of fire, a direct impingement IAR would not hold up to that as reliably as a short stroke piston system. No matter what measures are taken to prevent issues, the DI system will always fall short in a higher, sustained rate of fire weapon than a piston system will. That’s just the nature of the systems.

    Not only the gas tube could see increased issues over the standard infantry DI weapons, but you’re also introducing alot more heat into the upper receiver and bolt/carrier with the DI system that a short stroke piston system simply never does.

    • 8166PC1

      There’s actually a video out there by that shows the m16 cooking off rounds in full auto where the Galil doesn’t. The m16 and it’s gas system were really designed primarily for semi automatic use with fully automatic as an option

    • Genesis23OPB

      @8166PC1 still takes several thousand rounds full auto to melt the gas tube, which will never happen in actual combat. especially since the M27 was ment for another type of full auto fire compaired to the M249.

    • 8166PC1

      @Genesis23OPB yeah but rounds going off without pulling the trigger is a serious problem

    • timewave02012

      @8166PC1 The AR-15 is only slightly worse than any other closed bolt rifle with regard to cookoff, but on the rare occasion you’ve dumped the several hundred rounds required to approach cookoff temperature, then immediately need your rifle to be “safe”, yet at the same time as ready as possible, you can at least lock the bolt open on an AR-15.

  • Schpankme Verimuch

    “There are many like it, but this one is mine.”

  • The Third Pin

    13:10 I just noticed that STGW-57 sitting there against the woodpile. Do we get a video on it soon MAC?

    Edit: Sorry to hear about your friend that passed away. I give my condolences.

  • James Bridges

    The M27 maintained the accuracy standard to a higher round count, had a higher MRBF and stayed below the 120° threshold they used at 36RPM as opposed to 28RPM for the Colt (correct me if I’m wrong here guys it’s been a while). The FN HAMR I believe was the most reliable and had the highest rate of fire , but the barrel life was around half of the HK. What you have to understand in looking at the IAR program is that the accuracy was a key component of the concept- reducing that cone of fire ,creating more effective suppression with fewer rounds thus increasing mobility in the squad. They played around with several squad configurations before going with what’s been called ” the Super Squad” (see Sea Dragon study) . The HK has been a good choice for the Marines and they have fitted it as the M38 DMR (M27 previously had the longest effective range in the rifle squad so they took advantage of it).

    • Nick Graham

      ​@J van Niekerk the MR556 barrels have the same profile as the M27 IAR barrel to keep production streamlined because the same plant that produces the M27 IAR is also the same plant that produces the MR556

      also HK doesn’t exactly have the best track record for their CHF barrels anyone that has messed with their G3 rifles knows this also they have significant POI shift issue with their G-36 rifles.

    • Nick Graham

      @Ron Mclaughlin yeah but its awfully suspicious that of all the weapons submitted to the program the HK416 didnt really fit any of the programs requirements. the Gunner community pretty much just wanted a lighter version of SAW that performed the same role, it was the HQMC that tried to marry the request of the gunners with an earlier idea for a LSW while also coming up with some pretty weird requirements for the rifle which are pretty antiquated like using the weapon as a semi automatic point fire weapon and under the right situations full auto suppressive fire. which sounds like a requirement from the interwar era when weapons like the BAR and BREN where the common infantry automatic weapons. The problem with the whole IAR concept is it can be fulfilled by any standard rifle/carbine which further adds more fuel to the conspiracy that this was indeed just a backdoor way to adopt a new service rifle and to shut up whinny gunners who kept bitching about how heavy the m249 was.

    • J van Niekerk

      @Nick Graham Off course they would have the same profile barrels as both come from the same blue print, other that the MR556 has carrier and trigger design changes to make it impossible to convert to full auto. Both barrels come from the same blue print but are not made by the same folks accept for the the blanks, but after the blanks, it’s CHF and cut by 2 different folks. The G3 barrels, I have not heard of any issues of them (do not confuse German made G3’s with these Spanish G3 copies.) Poi shift on any barrel is normal when it starts heating up to a certain point, the big relevant question should be, does it go back to zero afterwards when barrel is cool again? If it doesn’t Zero, it is usually to do with the heat treatment process , an issue Colt even had with their barrels during the 60’s to late 80’s (many manufacturers struggled with heat treatment till about 30 years ago). Now, when it comes to the G36, the G36 was being used not for what it was intended for (lightweight contour barrel wasn’t designed to keep sufficient accuracy after 2 full auto mag dumps) , the original specifications of the German army was met by HK (even ruled as such in a German court). So it comes down to the fact that, that the light profile barrel was used for something it was not intended to be used for just like the M4 rifles, where their barrels were giving catastrophic failures with SOCOM (Barrels were splitting) , It came out, that SOCOM were using these M4’s as LMG’s with a specific “tactic/manoeuvre” . This was resolved by designing a new heavy profile barrel to be known as the SOCOM profile barrel that could handle sustained full auto fire.

    • Nick Graham

      @J van Niekerk
      1. yeah but they are effectively the same barrel there isnt exactly a special or secret way to cold hammer forge a barrel about the only difference in manufacture is how each company does stress relief but that is more done for accuracy than strength a Colt barrel is going to wear just as fast as a Kalashnikov Concern barrel, and HK barrel is going to wear at the same rate as a FN Barrel

      2. im not sure if you know this or not but the CETME came first and second the G3 is a rifle from the 1960’s so you can expect 1960’s accuracy so 3-4 moa there is a reason the G3 had to seriously be overhauled to become the PSG-1 and achieve sub moa groups which doesnt sound like all that great now but for the 1970’s its was pretty much a laser gun. i think people mistakenly assume that HK firearms are super accurate which couldn’t be further from the truth most HK firearms are military rifles and have military accuracy standards.

      3. the problem with the G-36 is the set of requirements where far to laxed for any serious military trials, for instance the rifles accuracy only had to be within 3-5 moa which is kinda lousy for the 1990’s however the Bundeswher was dead set on modernizing and looking “futuristic” also the G-36 was attempt to rebound after the colossal failure of the G-11 rifle.

      4. I see you watch Small Arms Solutions as well.

    • J van Niekerk

      @Nick Graham I beg to differ on the barrel life matter, there are too many variables that affect barrel life, type of steel being used (chrome moly, SS or Carbon steel), type of rifling, twist rate, the way it’s being shot, treatment or plating processes, type of ammo being used, and caliber. I totally agree that there is no secret to chf a barrel, there is though a specific way to do chrome lining. My issue with HK is, why do they go through all the trouble of bringing in barrel blanks from HK for their MR556, when they could rather ask Daniel Defense to manufacture barrels with a custom MR556 profile for them, that is 100% DD made and Chrome lined, DD barrels are excellent. I also agree that the requirements for the Bundeswher rifle program was very low… if you ask me, it’s like the program was a program during peace time, so technically speaking the G36 can be seen as a rifle for during “peace times”. I hope I’m making sense.

  • Mongo63a

    It only took them 50 years to get back to what the Stoner 63A offered.

  • Email

    Look at the difference in ejection patterns! Colt was like 3 o clock, 3 o clock, 3 o clock, 3 o clock… H&K was 1,3,2,2,1,3,2,1

    • Military Arms Channel

      The Colt is a sewing machine man. I love that gun.

    • Christopher Elmer

      Yes indeed the Colt is a smooth operator. That is why Colt sold so many Sporter Match Target H-bars back in 80’s and 90’s. They do great under sustained rapid fire conditions without the dramatic POI shift that the pencil 625 barrels did. I still prefer carrying the 625 lightweight pencil barrel because I always carry it more than I fire it.

  • Sam

    Imagine the look on Colts face when they saw the HK submission and knew they were about to get screwed out of all that R&D.

  • Little Low

    Marines said “make us our own 416 so we can act like they’re our guns!!”

    • TGTDS9513

      The real joke is thinking an HK416 is anything more than a slightly modernized AR-18

    • arkan purnama

      @TGTDS9513 AR 15/AR 18 hybrid

    • Little Low

      @TGTDS9513 nooo wym H and da K are so innovative with their very state of the art, very expensive because why not and don’t forget every H&K firearm has old nazi Germany gold put into each firearm making it just that more expensive!

  • AlexWie

    The Marines wanted a piston driven rifle. This was the way around the bureaucracy.

    • Ron Mclaughlin

      No, it was bought as a M249 replacement at the time of adoption there was planned production improvement for the M16 family of weapons in development for all other weapons. The people responsible for the procurement retired and their replacement saw an opportunity to get a new gun.

  • Gren Moyo

    MAC: and the m249 can fire from a magazine.

    M249 gunners: lul.

  • xxCOKERxxPWNxx

    From what Ive heard, the Marines took away “ automatic rifleman” role with the extinction of the single man belt fed and instead uses suppressive fire by having EACH marine carrying an m27. They can “ talk guns” and each take turns laying down rounds. And since the piston driven system keeps the gun cycling a little cooler, its capable of sustained fire for each individual rifleman over a longer period of time than an m4 would be. So instead of one machine gunner, effectively everyone is now in charge of laying down the Gunner role .

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