Knight’s Armament Stoner LMG (Finally) Enters Production

The KAC Light Machine Gun is a weapon that appears in media often, but has so far existed in the real world as a prototype only. Knight’s Armament Company announced at the 2016 SHOT Show that the thirty-year development of the weapon was nearing its conclusion and the LMG would soon be offered on the military market. Larry Vickers covers the new machine gun via his YouTube Channel:

Development of what would become the KAC LMG was begun by ARES, Inc, founded by famous AR-10 designer Eugene Stoner in 1986. Based in part on Stoner’s Stoner 63 weapon system produced by Cadillac Gage, the weapon, then known as the ARES Stoner 86, abandoned the Stoner 63’s convertibility features to create a cheaper, more reliable dedicated belt-fed 5.56mm light machine gun. However, this design failed to achieve a market, and Eugene Stoner partnered subsequently with Reed Knight’s Knight’s Armament Company to produce an improved variant, finalized as the KAC Stoner 96 LMG. The Stoner 96, also called the KAC LMG, languished without a buyer from the mid-1990s until today, appearing in Knight’s catalogs for nearly 20 years but never achieving enough orders for serial production. In 2016, KAC announced a finalized version that they reportedly are bringing to the military market.

The KAC LMG incorporates the same constant-recoil system developed by Jim Sullivan, designer of the AR-15 along with Robert Fremont, and used in the Ultimax 100 magazine-fed LMG.

Nathaniel F

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He is also the author of the original web serial Heartblood, which is being updated and edited regularly. He can be reached via email at


  • Giolli Joker

    KAC knew who the guy was. ๐Ÿ™‚

    • Nicks87

      I’m sure they had no problem with how much space he took up either.

  • Orion Quach

    9lb LMG, woot woot.

  • There’s no military market for this thing. Get on with the semi-auto civilian variant.

    • drambus ambiguous

      I’d say there’s a large paramilitary market for it though. Contractors are always going after PKMs and RPDs over M240s and M249s mainly because of how relatively light and handy they are by comparison.

      • aweds1

        I’d guess that also has to do with ammo availability in the regions they operate, too.

        • Probably also the relative cost differences of the guns, too.

    • Jeebus

      For SOF there is a market. Knights has always been geared towards SOF anyways.

    • iksnilol

      Uh, it can work as an replacement for the M249.

      Whilst LSAT is cool and all I doubt it will become as widespread as people think simply due to cost (fancy hybrid polymer case is more expensive than a non fancy metal case).

      • ostiariusalpha

        Actually, the LSAT ammo is projected to also be less expensive than standard brass cased cartridges. Plastic is cheap to mold.

      • Joshua

        LSAT cases will be exponentially cheaper. I believe the last quote was 100 cases for the price of one current 5.56 brass case.

        • iksnilol

          How many years till those savings pay off the R&D and the tooling?

        • I have no doubt that plastic will be much cheaper, but 100x cheaper seems implausible to me. Lets say a standard 5.56 brass case costs $0.20. That would mean that an LSAT case would cost $0.002, or 5 cases per penny. That would cost less than LEGO bricks.

          Now, I absolutely hope that I’m wrong (bring on the $0.10 5.56!) but that seems improbable.

          • nadnerbus

            Considering the economies of scale in stamping out millions or billions of plastic cases of the exact same dimension (versus thousands of different sized Lego bricks), it might actually be possible to to get the cost down that low.

          • “Approximately 19 billion Lego elements are produced per year. 2.16 million are molded every hour, 36,000 every minute.”

            Considering 12 Billion rounds of all calibers are sold each year in the US, the Army would need to commit to an insane buildup of LSAT 5.56 to drive prices that low.

          • iksnilol

            Still, Lego bricks are injection molded (I.E. “cheap” according to you) yet they are about the price of cocaine in the US. Even if you go for identical bricks.

          • I don’t recall Lego’s selling for $50 a gram.

          • iksnilol

            You’ve yet to see the Star Wars sets then ๐Ÿ˜›

      • Uniform223

        I haven’t been keeping up with the LSAT but this KAC LMG would be a more readily available and looks to be more stable (from a user end perspective) than the SAW. I am sure SF, Airborne, and Ranger units would appreciate this “new” LMG.

        • iksnilol

          And would be more practical in regards to international stuff.

      • HSR47

        TLDR: Non-metallic cartridge casings are a stupid idea.

        One of the biggest issues with moving from brass to polymer cases is heat: An extracted brass case takes ~30-40% of the heat it generated with it when it is extracted and ejected. By contrast, a polymer case takes almost none of it’s heat with it upon extraction/ejection.

        This means that you need to carry more barrels, and change them more frequently.

        When you get down to it, MG barrels are fairly heavy; I don’t have exact figures, but my educated guess is that an M249 barrel is somewhere around 3-4.5 pounds depending on configuration. 100 rounds of brass-cased 5.56 weighs approximately 3 pounds, of which approximately half is the brass. By my quick back-of-the-envelope calculations, the weight savings from lighter casings is largely or wholly offset by the weight of the increased number of barrels that will be needed.

        Further, ROF would also be effected, because barrels would need to be swapped out significantly more frequently, which has an operational cost. That’s also before you even consider the fact that polymer cases don’t hold up as well as brass cases, which will almost certainly lead lead to significantly more frequent stoppages.

  • I could have sworn that the Danish military had bought some for one of their special forces units.

    • ostiariusalpha

      They were certainly the ones testing the pre-production units. The whole reason KAC is able to show this as a production model is probably because the Danes are going to be the buyers.

    • Emfourty Gasmask

      I’m pretty positive they got the M60E6

    • Some photos have been floating around since 2009 claiming to be a KAC LMG in the inventory of the Royal Danish Navy’s Frรธmandskorpset (FKP).

  • Joshua

    Shame it took them so long.

    Metal cased ammunition is on borrowed time. Had this come out 20yrs ago it would have been amazing, but LSAT will be here within 10 years and will replace brass cased ammunition.

    • I’m agnostic about LSAT. The telescoped ammunition configuration has some major problems (though I’d be interested to hear the LSAT team address them, for sure).

      Lightweight cases are coming, one way or another, though.

      • Anomanom

        I’m not sure cased ammunition isn’t on borrowed time at this point. 3d printing is in the market in a big way. I think it wont be long before some enterprising mind out there figures out a way to 3d print solid propellant around a projectile in an efficient manner.

        • Out of the Blue

          There needs to be a bit more refinement in the speed department before that can happen. The current printers on the market, barring one that uses a special resin and ultraviolet light, are far too slow for mass production, easily taking an hour for decent sized prints. Ammo would be on the small side but you need to pound out large quantities. Even that one would be on the too slow side based on what little I know about mass production.

      • Joshua

        LSAT Is huge. It’s a joint project between Canada and US.

        We are developing the LMG and Canada is developing the Carbine, with a few EU countries keeping an eye on it as well. This is one of the largest joint small arms development in history.

        It’s coming. The LMG is already has seen hundreds of thousands of rounds tested on it. Canada also has a working bullpup that has a 26″ barrel in a package shorter than the current M4.

        AAI is also developing a 7.62 LMG and is pushing heavily for a 6.5 bullet to be integrated into the system

        • Yes, but so far I haven’t heard how they’ve solved the gas blow-by problem. Until they do, I doubt the telescoped configuration will be viable, as it will basically melt throats.

          Don’t get me wrong, I’m rooting for it. I just think they’ve got their work cut out for them.

        • n0truscotsman

          I heard a rumor about a couple of those points, didn’t know how true they were.

          Im eagerly awaiting news about the program though.

        • iksnilol

          Why so long barrel on it? If they made a short bullpup mechanism like the Korobov they should go with a shorter barrel for general handiness.

          Unless if it is the LMG where added barrel is needed for heat dissipation.

          • Probably want dat EM-2 swag…

          • iksnilol

            I gotta admit, EM-2 swag is pretty swag.

        • Joey JoJo Jr.

          Name one AAI-designed small arms system that has been successfully fielded, besides the M203 40mm launcher. Most of their stuff is vaporware or doesn’t live up to the “dream sheet”, like the M85, SPIW, OICW, etc. etc… LSAT has been the “next big thing” for what, twenty years now?

      • HSR47

        non-metallic cases don’t make sense for machineguns, and they might not make sense for infantry carbines.

        The biggest issue is heat: Every time you fire a round, heat is generated. Brass cases act like heat sinks, and upon extraction they take ~30-40% of their heat with them. Polymer cases take effectively no heat along with them, which means that it all stays in the gun, and mostly the barrel.

        That translates directly to a lower sustainable rate of fire, and shorter duty cycles for barrels. In terms of machineguns, that means you need to carry more barrels, and in terms of infantry rifles it means that you have to effectively cut your total ROF in half. According to the internet, the infinitely sustainable ROF for the M249 is 85 RPM; At that rate no barrel changes are necessary. The barrels on infantry rifles are typically thinner, so ~60 RPM is probably a reasonable estimate for an M16A4 or M4, but it may be lower in practice (The move towards heavier profile barrels moved the point of failure to the gas tube). That means that moving to polymer cases will likely take your sustainable ROF for infantry rifles/carbines down to 30-45 rounds per minute, and will likely shift the point of failure back to the barrel.

        On machineguns, barrel changes allow you to keep roughly the same ROF as before, but with more frequent barrel changes. That means you need to keep more on hand to swap between. From what I see online, M249 barrels look like they weigh 3-4.5+ pounds each; brass-cased 5.56 ammo weighs roughly 3 pounds per 100 rounds by itself, of which roughly half is the brass. That means that in terms of weight, moving to non-metallic cartridge cases is nearly a 1:1 trade-off in terms of weight: The lighter weight of the ammo is offset by the greater weight of the increased number of barrels.

        There’s also the issue of ammunition durability (metallic cases can take a lot of abuse, plastic not so much), and in caseless designs fouling can also be a big issue (metallic cases tend to direct the bulk of the dirty gasses out the muzzle, rather than through the chamber and breech.

        In other words, there’s a very good reason we haven’t moved to polymer-cased (or even caseless) ammunition: It doesn’t make sense.

    • iksnilol

      Eh, it was made 20 years ago and nobody wanted it :/

    • Max Power

      LSAT has been “10 years out” for the last couple of decades. Like a lot of blue-sky Dod-funded stuff AAI futzes around with.

      • “Last couple of decades”, huh? The program started in 2004 and went from TRL 4 to TRL 7-8 since then.

  • santi

    Maybe a dumb question but was there any talk of making a civilian version? I err on the side of no but I saw FN made a civilian version of their classic LMG, so I figured maybe this is a new trend for civilian belt feds to get into the market.

    • I’d certainly like one, given the recoil system, 9.5lb weight, and glorious beltfedness.

      • PK

        Indeed. Perhaps FN started a trend – they’ve certainly shown that a $10k semi-auto belt fed has market appeal. I expect that if KAC were to make a semi-auto only version, it would be in that price bracket as well… and it would sell just fine.

        • Hopefully that will pave the way for Ruger to then release a $1500 belt fed ๐Ÿ˜‰

        • Anon. E Maus

          All we need now is a slidefire stock that fits on these LMGs

    • Jeebus

      I see the buttstock comes off- maybe a pistol version is in the works? ๐Ÿ˜‰

      • mig1nc

        Lets throw a binary trigger on it too ๐Ÿ™‚

  • TheSmellofNapalm

    Very exciting!!! This will blow those 20-pound relics out of the water

  • MPWS

    Seems to me Larry is saying: “…feed if from czech guns”. What guns? Is it Vz.59 UK with its carrier actuated feed pawl?

  • Riot

    minimi para is 14.5 lbs with a slightly shorter barrel, which is why I’ve never liked it – the pkm is a 7.62R with a 24″ barrel at 16.5 lbs for comparison.

    This on the other hand is an actually lightweight lmg.

    • BillC

      Yeah, but throw on 100 or 200 rounds of either and then see what happens. Also, a M249 has a completely different purpose/use than a lightweight GPMG, even though the end goal of both is shooting at the enemy for suppression/killing.

  • micmac80

    When you have workable 60 ,100 round mags why bother with the beltfeed for 5.56

    • G0rdon_Fr33man

      Price, reliability and logistics.

    • CommonSense23

      What reliable 60 and 100 round mags due you know of. And box of 5.56 link comes is 200 rounds. Pretty big advantage.

      • micmac80

        the pouch larry is showing is 100rd , beltfeed adds complexity and weight also opens the action further to debris.
        Plus once you have to change the belt its way slower than the mag.
        200round pack might sound nice but is a pig to carry and practical fire rate doesn’t justify it. Only real benefit of the beltfeed is the low down position that it can be fired off unlike long magazine.

        Lets not forget everyone in the squad carries magazines , but there are only so many linked belts

        Ultimax offers a 100rd drum ., Practical or sustained rate of fire is more a dependant of the barrel change than ammo feed

        • Squirreltakular

          Don’t the C-mags have a pretty bad track record, too?

        • Carrying 100 round drums around would be a huge problem. They are quite sizable and heavy. The Polymer Magpul D60 weighs 20 oz’s unloaded, and is pretty bulky relative to capacity. Carrying multiple drums would take up a ton of space.

          A 200 round plastic box of linked 5.56 weighs 6.92lbs. To reach 180 rounds with the Magpul Drum 60’s, you would have 3.75lbs of just magazines (to say nothing of volume.) Loaded, each D60 is 44ozs, so 180 rounds in Drums would weigh 8.33lbs.

          You gain weight and bulk while loosing capacity and sustained fire by using drums.

    • Squirreltakular

      The Surefires have a bad record, the Magpul D60 isn’t tested enough yet, the X-products mags are limited to 50…

      I’m not seeing any advantages over belt feed.

  • LazyReader

    I got barred from commenting on Larry Vicker’s Facebook. I made a joke about the circumstance at the Ruger display at SHOT SHOW. Apparently he got snubbed at the Ruger booth for apparently not knowing who he was; feeling ever the prima donna he took to social media using his internet celebrity status to slam the company for the slight inconvenience. My remark?

    “So Ruger didn’t roll out the red carpet for him, boo hoo”

    That’s the comment that got me kicked off Vicker’s Facebook, apparently now I cant comment there anymore. Someone needs to go crawl in his safe space. But if that’s the way he’s gonna act, fine. I’ve unsubscribed from his YouTube page, Ceased following his Twitter and Facebook page.

    • iksnilol

      What does that have to do with KAC’s LMG?

      • Cymond

        Nothing, but TFB did embed LAV’s video about KAC’s LMG.

    • It’s his page. Apparently they were taking up more space in the booth which I guess is what started whatever happened. I wasn’t there so I can’t say for sure.

  • DancesWithGlock

    So same weight as the KRISS.

  • LazyReader

    9 pounds. How much cardboard and hot glue they use?
    There’s a reason even some light machine guns weigh a little, being robust.

    • iksnilol

      Eh, slower rate of fire (constant recoil principle) and 5.56 will probably give it no problem in durability.

  • ostiariusalpha

    That was one of the evaluation guns, it still belonged to KAC at the time the photo was taken.

  • Michael Snow

    They need a 2 stage barrel release. That one stage barrel release is an accident waiting to happen and it can be done by just putting a cover over it that has to be flipped up before pressing that barrel release button.

  • ColonelColt

    15″ barrel to let you know it’s not for mere mortals.

  • Eric B.

    OK, if it’s better in several ways compared with the current FN made SAW then we should probably get it.
    AND… we should get the General Dynamics medium machine gun that uses the .300 Lapua magnum cartridge. It’s the same weight as our current FN medium machine gun, has a recoil reduction mechanism to equal the current medium machine gun recoil and has a LOT greater range. (Yeah, retire all 7.62 x 52 NATO weapons. It’s past time. I mean even the 6.5 Creedmoor cartridge in my Ruger Precision Rifle has much better range than the .308/7.62 NATO.)

    With the new General Dynamics MG we could have a distinct advantage on the battlefield, especially with the backpack belt fed ammo carrier developed in Iraq and perfected by the Army’s Nautick testing center. Imagine, that MG accompanied by a Designated Marksman with an XM 2010 sniper rifle chambered in .300 Lapua rounds as well. That’s a real lethal team. They protect each other and the squad.