Barrett M240LW Prototype

Barrett brought their lightweight M240LW prototype to the Big Bang Shoot and SHOT Show. Unlike the M240L, which is in service with the Army, it does not use any exotic/expensive materials or manufacturing techniques to decrease weight. They instead decreased weight by trimming off as much metal as possible and decreased manufacturing costs by making the receiver in two pieces and then bolting it together. They managed to trim about 6 pounds off the standard M240B. Unfortunately Barrett ran out of 7.62mm ammunition before I had a chance to shoot it.

M240LW Serial #000001

[ Photos 1, 3 and 4 Β© Bryan Jones ]

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Anton

    That’s great, I know the Dutch troopers love this gun. In Afghanistan they used to tear these off off their own vehicles to take into the field because their 5,56 rifles didn’t have enough punch.

  • calool

    im loving the cut down look on this, the m240b looks too bulky for what it is, this seems about right for an infantry carried/vehicle mounted lmg

  • FourString

    6 pounds off o.o
    that’s basically the weight of an AR! Those concave ridges look like they uphold the structure of teh receiver pretty well.

  • Man… I wish I had that sucker when I was in the sandbox… Every ounce counts I guess, and a 28lb machine gun gets a little heavy at the end of a 12 hour foot patrol.

  • charles222

    Wow. Did Barrett let the stupid people out to play with this one? The reason the 240 weighs so much is because it has to. The recoil stresses and wear & tear on the 240 are intense and shaving metal off and bolting the receiver together is not the answer. It might look nice, but that’s about it. You want a good, light 7.62mm MG, go with an M240L or the Mk48.

    • Komrad

      Because you’re an engineer and you did all the math and painstaking optimization to come up with this design. I’m not saying your post might not have an element of truth (there might be some reduced reliability), but calling a design stupid when you’ve never seen or handled one, there are no trials or data out yet, and you’ve not looked at even rough design specifications IS stupid.

      • charles222

        Yeah, I guess my four deployments to Afghanistan and Iraq in a light-infantry platoon leaves me completely unqualified to comment on machine-gun design. You can take your “you’re not an engineer” and stuff it. I know what works and what doesn’t and this is an amazingly bad design concept.

      • Joe Schmoe

        Hello Charles,

        If anything, your four deployments with the MG leaves you overqualified >to comment< on a new version of it.

        But one thing you have to realize is that the M240 is a 60 year old beast of a gun made in an era of slides, etc. With today's 3D modeling technology and manufacturing materials and methods we can make the M240 much lighter AND much stronger at the same time.

        The problem the other posters are having is that you are judging this MG to be junk before it has even gone through testing. You may very well be right, but why not give it a chance at least?

      • W

        i say innovate and test it. It cannot hurt to improve right? I love the M240B. The FN MAG, in my opinion, is one of the finest machine gun designs ever conceived. Im utterly fascinated that it still utilizes concepts from the BAR and MG42. πŸ˜€

        i would agree that multiple deployments in light infantry makes you a subject matter expert, though, suffering from the same problem myself on occasion, there is a propensity for bias and emotional attachment.

      • Komrad

        I disagree with Charles and W. Deployments and use does not make one an expert in the design part of the design of a firearm. It certainly would qualify you as an expert in maintenance, use, and even repair, however, it does not give you much if any knowledge of the math that goes into a design like this.

        Pilots generally can’t design airplanes, F1 racers can’t usually design their own cars, and very few soldiers can design their own weapons.

        Your experience may very well be very valuable as input in a new design (ie, you could almost certainly tell an engineer what parts break most often or what causes the most jams), but you never had to do the math and testing to see how large the gas port should be, how strong springs should be, what weight the bolt should be, how thick locking lugs need to be, etc.

        It looks to me (and as another poster mentioned) that Barrett left ridges to reinforce critical areas. As a math junkie myself, I can attest to the power of optimization and dimensional analysis. This is likely what Barrett did. It would not be too difficult for them to calculate the stresses on the receiver and simply set up a math problem or simulation to minimize the weight while keeping the strength at or above required levels.

        They might have even fiddled with the heat treating process or precise steel alloy used to further weight savings.
        It is almost certainly more complicated than just “shaving metal off.”

      • W

        “It looks to me (and as another poster mentioned) that Barrett left ridges to reinforce critical areas. As a math junkie myself, I can attest to the power of optimization and dimensional analysis. This is likely what Barrett did. It would not be too difficult for them to calculate the stresses on the receiver and simply set up a math problem or simulation to minimize the weight while keeping the strength at or above required levels.”

        I have a lot of respect for people that make a living employing advanced mathematics when designing firearms; or are good at math in general. I have always performed marginal in mathematics (enough for me to calculate range and ballistic adjustments…hardly complicated math), thus I graduated as a economics major. I could tell by your first comment, komrad that you were a math junkie btw…

        I can see from the receiver that Barrett’s designers cut the receiver in a manner which would increase strength without excess material. It wouldn’t be difficult for them, though i remain dubious of the average person’s ability to understand why they did it πŸ™‚

    • W

      i doubt Barrett lets any stupidity play in his organization. I find it ironic that you mention the Mk 48 as a better alternative, when thinner materials and design were incorporated to reduce weight…at the price of shorter service life.

      There is no way of knowing just how reliable this weapon is, since it is so new, unless a comprehensive stress test is conducted on it, comparing it to the M240 series.

      Considering it is a entry from Barrett, I remain optimistic.

    • Reverend Clint

      the m240 is a 50 year old design that has had very little changed to it… until now.
      being in light infantry does not preclude your opinion but that would be like saying an f-16 pilot would know how to engineer a gen 5 fighter.

    • TCBA_Joe

      They also managed to do it without chopping the bbl length.

      charles222, Please do some more research before coming off half-cocked.

      There was a more extensive article on this gun in the gun rags a couple months ago. Basically the way the receiver is billet, not stamped. In a stamped and riveted gun there needs to be overlap of material with which to rivet. There’s also excessive material in the charging handle area on the M240 due to the stamped design.

      By remove the weight of excess material and the rivets and fluting the barrel, and Barrett was able to reduce weight of the 240 by 6 lbs without sacrificing the strength of the legacy receiver. The design is a no-brainer in retrospect.

      There’s a lot more engineering in this gun than “shaving weight and bolting it together”.

      As for the MK48, it does have strength and life-span issues. It being issued to US forces was a stop-gap until the Army could get us the M240L. Which is taking much longer than it should.

      If we’re going to start pulling out the experience cards, I’ve got more rounds down range on the 240B alone than most people shoot in their entire life.

    • There has been a number of requests from mil sources to reduce the weight of a suppressive fire system. The MG240 and its associated ammunition is *heavy* and with good engineering, it does not have to be that heavy. There is a reason that technology has stepped in to reduce the carried weight of systems. The Thompson M1 that my Grandfather carried in WWII weighed 10.6 lbs empty. A modern M4 carbine is somewhere in the neighborhood of 6.2 lbs. I can guarantee you that those pounds matter. If Barrett is able to shave 6 lbs off the weight of an MG240 and preserve reliability, then I say more power to them. That is 6 lbs that a soldier does not have to carry mile after mile and it does add up.

    • jagersmith

      The M240L, while great for dismount purposes, has fractured (titanium is more brittle) when used in pintle mounts, especially with T&E mechanisms. For mounted to dismounted transitions, I hope the Barrett will work better. That being said, M240/MAG58 variants all had rivets as well as welds, I doubt the Barrett is just held together by a simple eyebolt. I can see your concerns about the company, as SASR/M107s are easily adversely affected in combat conditions. I have much M240 experience both with the golf and bravo variant, as well as time with the MAG58 GPMG.

    • G

      I am just curious..

      But how many of you, who are criticizing Charles, have any military experience have and/or have experience with the M240/FN MAG?

      • Komrad

        Military experience does not an engineer make. It is a very respectable profession, but it is not firearms design. Military experience is not required to design arms. Input from those who have used the weapon that a given design is replacing is be quite valuable, but there is a large difference between knowing what works and is broken and knowing how to fix problems and improve strengths.

        John Garand never served, nor did Samuel Colt, Emile and Leon Nagant, Paul Mauser, Hugo Schmeiser, John Moses Browning or many other respected designers.

      • W

        mikhail kalashnikov did πŸ™‚

      • Komrad

        That he did. Military service neither precludes nor ensures that a given person can design firearms.

      • Joe Schmoe

        I used it on vehicle patrols (when dismounted) and was in a firefight one time with it.

        In that firefight the damn thing jammed twice in a row on me; for a weapon that has a 1/26,000 failure rate, what are the odds it would do it twice in a row on the same day I checked and cleaned all the ammo belts? πŸ™

      • Komrad


        For any two given shots, the odds of both producing a failure (using your 1/26000 failure rate) would be 1.4792 x 10^-9 or mor accurately 1/(26000^2).

    • Randy

      I say thank you to Charles for his service. And to all that have or will serve. Past-present-future. As to the weapon only time blood sweat and the brave warriors that will field this weapon will tell. Hopefully not at the cost of lives because of failure.
      Support Our Troops!!! They are all heros!!!

  • W

    according to the SAMG blue book, a M240B weighs 27.6 lbs. Weighing approximately six pounds less brings the Barrett about the 20-21 lb range give or take.

    That is not bad for a general purpose machine gun. It puts it to comparable weight to the M60/M60E4 (23 lbs), which is the compelling reason why the M60E4 is still deployed with special operations forces on a limited scale (it is lighter than the M240B).

    “it does not use any exotic/expensive materials or manufacturing techniques to decrease weight.”

    This is a significant advantage, especially since wartime conditions may necessitate the need for essential materials to be used for more conducive purposes.

    “They instead decreased weight by trimming off as much metal as possible and decreased manufacturing costs by making the receiver in two pieces and then bolting it together.”

    Again, another significant advantage. Trimming off the unnecessary materials theoretically shouldn’t reduce reliability, though we will have to see in the future. I certainly hope this machine gun gains more attention from the defense department.

    • Yes, this is why I think they are marketing it (or will be marketing it to the military) as an alternative to the M240L. If total war come along, titanium (and other advanced strategic materials) would be diverted to applications where steel is not an option.

      • W

        I think in an era of decreased growth in military spending, the Barrett 240 will be more attractive than the Lima variant if it proves itself. Im curious to see a mass production unit cost when compared to its cousins.

  • lex

    What “exotic” materials went into the M240L?

    • JMD

      Titanium, I believe.

      • Martin (M)

        Titanium shouldn’t be considered exotic anymore. Even though it costs about $20 a pound the new metalysis process should bring titanium down to <$10 a pound. Still, tooling and labor are where the big money is at.

      • Komrad

        Titanium is fairly exotic. Sure, it’s used in high tech and heavy industrial stuff, but as far as common use, there is very little, especially in the manufacture of receivers.
        According to Wikipedia, it also incorporates “alternative manufacturing methods for fabricating major components” which means absolutely nothing by itself.

    • W

      titanium is a critical component of many fixed wing and helicopter aircraft, turbine engines, and missiles. Theoretically, in the event of a large-scale war or intense demand for titanium, these machine guns could still be produced without interruptions in production. Of course, readily available materials also keeps the cost low, allowing it to compete with existing designs and competitors. In my opinion, it is a very intelligent concept on Barrett’s part if it is indeed reliable and strong enough.

  • Nooky

    It should be fun to make a titanium version of this design to see how light you can go.

    It would probably still weight more than a PKM though

    • W

      don’t forget a super alloy to line the bolt, chamber, and barrel with. Im thinking of a super duper Osmium/Carbide alloy that is insanely expensive but virtually indestructible πŸ˜€

  • Lou

    I still say that we should simply go with a new modernized version of the Rheinmetall MG3 (MG42 in 7.62x51mm). It’s a proven system, weighs in at 23lbs right now, and can be made to use the M60 links that the M60 and M240 use. Easier to produce also and can easily be modernized to cut down weight.

    I’ve lugged a M240B around and it’s a heavy SOB and is based off the old Browning design. The MG3 has my vote. But of course common sense isn’t common.

    • Doesitmatter?

      Say MG3? I do not know if that is the best take on future MG. Let me suggest something else: last ittiration of 7.62x54R PKM is called Pecheneg and it is one heckovagun:

      Russians figured out that there is a way how to avoid changing barrels with cleaver heat management. How about that?! So now when, as we just read, ruskies are approaching our rifle design with AR12, we can as well take lesson from their MG (adapted to Nato ammo, of course).

    • mosinman

      or heres an idea…. why not just design our own machinegun instead of using someone elses design?i mean the U.S has all the tools and plenty of bright people….

      • Doesitmatter?

        That already has happened… and result was M60. Some troops disliked it intensely and it eventually gave way to M240. The M60 however was not entirely american gun – his granpa was this german ‘dogcat’:

        But, that’s how it goes: there is no one who would come with uniquely own idea. It’s kind of borrowing game. If I was to name a true american gun it would be – Gatling.

      • W

        In defense of the M240, it utilizes similar locking mechanism and bolt design that john browning designed (BAR).

        Yeah the M60 was a result of what happens when a firearm is designed by a company/corporation rather than a individual firearms designer.

        The worst case scenario is that a foreign-design weapon is adopted and produced by american workers.

        If you look at FNH, American John M Browning approached them after the end of the Browning and Winchester collaboration. FN was originally founded to produce German-designed Mausers for the Belgian armed forces I believe. This company has always had a unique history.

      • mosinman

        i have no problem with the m240 its a great design but i just dont get why a us company wont design something better, i guess this is it though, idc that much as long as it helps our troops. poor m60 lol

  • Doesitmatter?

    I hapen to be somewhat intimate with this gun, not as a user though, may I add. This indeed is old beast and one of the best. The reasons are few. One is that is is successful symbiosis of MG3(feed) and BAR(operating mechanism). As you may know the MG3(MG3) is prone to excessive rate of fire (think of continuous ammo supply).

    Now, the issue in my mind here is its structural complexity; that boxy receiver consists (in original form anyway) from dozen of precision machined pieces RIVETED together. Comon now: riveted? Yes! From this standpoint it is technologically long outclassed already. We are long time in era of much smarter techniques to join metal. By the way, FNMI has had also ‘sheet metal’ version of Minimi in 7.62×51.

    Given the fact that Barrett can only (within reasonable expense for R&D) so little to do anything meaningfull with the gun, this undertaking is on edge of dispare. Military ‘market’ is the most ‘bitchy’ one; no place to collect laurels.

  • Jack Luz

    This M-240 needs a more rigid and sturdier bipod. The FN version is too flimsey. Most soldiers prefer to fire the M-240 on a tripod/mount or resting on a fallen tree log or window sill and so on. Taiwan’s army uses the FN MAG/M-240 and had modified it with an M-60 type bipod in place of the Belgian design.

    One additional footnote: the U.S. Army’s PEO solved the problem of ammunition by developing a clip-on ammo container for the M-240. This enables the weapon to be carried by just one soldier, as opposed to two.

  • abc123


    Does the M240L have interchangable parts with FN MAG and M240? I presume this Barret will not be interchangable.

  • Mat

    It seems US small arms designs arent worth a penny nowdays ,most small arms used by US troops now are european designs M240,SAW,IAR,SCAR,M9 etc. H&K barely failed from replacing the entire M16/4 family with HK XM-8 ,M4 is even built by FN in US and it doesn’t seem much better on civilian market Glock,Hk,FN,SIG,Berreta,CZ take up great chunk of the market even Springfield XD is american just by trade name its designed and built in Europe where its sold as HS .

    Russian PKM does all M240 can on stamped parts and weighs less no facy titanium needed

    • W

      you those weapons are manufactured in the US right? and you do know the US is the largest arms exporter in the world right?

      • William

        Not entirely correct.
        China and Russia export more heavy guns than the USA.

  • FYI: The Barrett M240LW’s design is covered by US Patent #7,937,877.

  • I wonder what does bolting the two piece receiver do for accuracy. But regardless, the simple fact that it’s light is a huge plus.

  • northor

    No barrel shroud? what happens when he decides to fling that thing over his shoulders? I know I would never dare to touch a MG3 barrel after I’d fired of a few hundred rounds.

    • David

      A soldier/Marine will only put their hand on a hot barrel once…..they’ll never do it again

      • northor

        thing is there is nothing but barrel on that thing. In my experience mgs that size isn’t really the most easy type of weapon to carry around. our mg gunners always slung their mg3s over the shoulder because that was the easiest way to carry them around (I was in the norwegian army as a rifleman).

        I’m telling you, a LOT of soldiers will be burned simply because their hands slipped a few cm with that thing. I’d rather keep the 24 pound MG3 and its 1200 RPM.

      • David / Sharpie

        Maybe, but that’ll be the only time they do it, and they should wear gloves too.

        There hasn’t been any whining from CF soldiers or Us Marines about them burning themselves, I guess the grunts aren’t as dumb as everyone makes them out to be

      • northor

        Yes, but the M240 version the marines are using now all have barrel shrouds. This thing does not.

      • David/Sharpie

        No they are not, the Marines use the same variant of the FN MAG as the Canadian Forces, M240G (C6 in Canadian Service) which does NOT have a handguard/barrel shroud.

        That quote “A soldier/Marine will only put their hand on a hot barrel once…..they’ll never do it again” CAME from a Marine General who was talking about the lack of barrel shroud

      • northor

        Isn’t the M240B the marine standard these days? I could be wrong, I was under the impression that the M240G was a vehicle mounted or tripod version. The sources I’ve read are a little unclear, so I’m a little confused.

        Apologies if I’ve been mistaken.

      • David/Sharpie

        M240B is US Army, the G variant is Marine, basically the same but no barrel shroud.

        All MAGs can be mounted on vehicles or tripods.

        Look here at the diff variants.

        These are respectively the B and G variants, looking at pics of them is better than reading about them

      • northor

        I stand corrected and owe you an apology. I Did read up on that a while ago, must have misremembered.

        And as a rifleman I Still think the no barrel shroud thing looks inconvenient when carrying the thing around, over the shoulder and otherwise. And I’ll be damned before I let a friggin general tell me differently, because I doubt that he has proper experience with the thing.

        It’s just my opinion though. I could be wrong, you certainly just proved that ;).

      • David/Sharpie

        See that sling? Canadian Soldiers carry it slung on their shoulder and hanging in front of them, if needed hold the pistol grip with firing hand and the top handle with their support hand. They do not have trouble with a hot gas tube.

        Personally I’d rather a few pounds less and just be more careful with the hot tube

      • northor

        We had thoose too, never used them unless we were marching, with something that long and bulky you need both hands on at all times, or it gets plain unwieldy when you have to sprint around with them like crazy during fire and manouver where being carefull is usually not an option.

        if you look at how we use our MGs in the video you’ll notice that we don’t rely on the sling for support when we’re on the move, its either in a tight grip or over the shoulder. I’ll admit that the MG3 is a heavy fucker, but its a damn fine weapon regardless

        I also would just like to add that I enjoy the civil tone of the debate.