Polymer Disintegrating Belts for PKM Machine Guns

According to Ukrainian Industrial Portal, a company called RAROG (Kharkov, Ukraine) has developed a polymer made disintegrating belt for the PKM machine guns. The standard PKM belts are non-disintegrating (the links are connected to each other) and they are made of metal. Polymer construction of the new belt should allow saving some weight.

Whether switching to the disintegrating belt is a good choice or not … it is hard to tell. It is an arguable matter and both systems have pros and cons. The deputy CEO of the company told that they started to develop the disintegrating belts because of multiple requests from the Ukrainian army soldiers.

There were experimental polymer belts in the Soviet Union. However, probably the lack of experience of working with polymers and/or the lack of proper materials didn’t allow to further develop these projects.

I think the performance of polymer links in extreme temperatures should be the main concern here. If the material performs well both in the arctic cold and desert heat, then it is an improvement indeed. In the video below, they are testing a belt which was frozen to -50°C (-58°F). Looks like they placed the belt into a metal jar full of dry ice to simulate the low temperature.

The manufacturer has finished the development of this belt and will submit it for Ukrainian government trials.



Hrachya H

Being a lifelong firearms enthusiast, Hrachya always enjoys studying design, technology and history of guns and ammunition. His knowledge of Russian allows him to translate and make Russian/Soviet/Combloc small arms related information available for the English speaking audience.
Should you need to contact him, feel free to shoot him a message at TFBHrachyaH@gmail.com


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  • PK

    Interesting idea, especially with how suitable polymers are becoming for pull-feed links. If it were a push-style, I wouldn’t trust the polymer to provide spring retention in cold weather.

    • jono102

      Makes sense, seen both NATO 7.62 and 5.56 rounds get unseated both forwards and backwards in the link. With this it can only come out backwards and the action of the belt feeding into the gun would help push it forwards and re seat it.
      Now the just need to pair it to a smaller profile canvas belt bag

    • LSAT/CTSAS has evidently had good luck with their wraparound polymer links, so it should be possible. Whether these live up to that standard or not, I don’t know.

      • PK

        That’s a very fair point, but keep in mind that the push links in that program were designed from the outset to interface with the cases (also designed from the outset) to be polymer. With conventional cartridges, the size of extraction grooves, shape, action reciprocation… I just wouldn’t trust it in the cold without serious evidence that it works 100% as well as metal links.

        Also, recall this answer (dealing with the polymer links) from the CTSAS program interview:

        “They work perfectly with cylindrical (CT) cases, but would not work with
        legacy ammunition due to the way the links are stripped.”

        Luckily, for pull-feed, the polymer links will do just fine even in the cold so long as the particular material selected is suitable. Even fairly cheap polymers worked fine in the .22lr pull-feed I fired in -35°F conditions!

      • Mr.SATism

        I think that the problem with those programs was the complete conversion of ammo, if they would’ve kept their links and put it on a standard 556 and american 762 it would be a much more attractive offer for belt fed machine guns

        • ostiariusalpha

          The entire point was to replace the ammo. The CTSAS machine guns are superior in just about every way to legacy 5.56 and 7.62 guns thanks to that new ammo.

  • The Mystic Seer

    I loved firing the PKM at Battle Field Las Vegas, too bad it was on a bolted monopd. Would have preferred shooting it from the hip.

    • roguetechie

      I’ve never shot one from the hip, but I’ve shot a fair amount off the bipod and a few belts off the tripod designed for it.

      It’s a good gun, and was way more controllable for me than the mg3.

      • Renato H M de Oliveira

        The far lower ROF surely helps.

        • roguetechie

          Definitely, but having fired pkm’s first in my early teens and only experiencing an mg3 the first time in my early 20’s when I was a good 4-6 inches taller and 30+ pounds heavier… I figured, oh this isn’t going to be anything I haven’t done before!

          BOY WAS I WRONG!

          I flopped down, took a lazy prone position, got the gun up on the bipod, pulled the trigger, and OH MY GOD!

          The gun is now screaming, beating on me, and jumping around alarmingly!

          Thank God the owner had only set me up with about a dozen rounds.

          He then smiles at me and says “Do you want to see how you have to use this now?”

          It’s not like I had no experience firing automatic weapons, but if anything that experience worked against me because I didn’t take it seriously.

          • Renato H M de Oliveira

            LOL

  • Ark

    We’re over here bellyaching about new calibers while half of the entire world is still chugging away with their PKMs with no real interest in replacing them. Why didn’t we adopt this, again?

    • For various reasons it isn’t a good fit with the preferences and doctrine of the US Army or Marine Corps… Whether that tells you that the doctrine is wrong or not is up to you.

      • derpmaster

        There isn’t a snowball’s chance in hell that the US brass would approve adopting a Soviet/Russian design. It’s a great GPMG but can you even imagine the jokes/embarrassment that would come out of that?

        • James O Donnell

          The days of “not invented here” are long past.

          M249

          M9

          M320

          M3/M4 Carl Gustafs

          There’s no chance of the PKM being adopted simply because we already have a GPMG — the M240 — that is at least as good.

          • derpmaster

            Note that those are all NATO state designs.* I’m not the end-all expert but I can’t think of a single Warsaw Pact weapon that the US uses.

            There is overlap in the former Pact states in Eastern Europe, but it would be career suicide for anyone in the Pentagon to even suggest adopting a weapon out of Russia. The Cold War lives on in the hearts and minds of many.

            *Of course there’s always the Sweden technicality, get over it

          • roguetechie

            You obviously didn’t see the RFI from the other day…

          • derpmaster

            which was a tender for US-made PKMs to arm foreign allied forces. huge difference.

          • roguetechie

            And NSV’s lol…

          • Sermon 7.62

            The Cold War has not ended, it is going on and on.

          • James O Donnell

            What Soviet/Russian gear is so much better that it would be worth adopting? Be specific.

          • Heck, the M249 is even mechanically very similar to the PK.

          • roguetechie

            Too bad FN added all that suck to it…

            Maybe it started out as a naval machine gun and all that suck is actually cleverly disguised ballast…

          • iksnilol

            Yeah, but…. M249 is Belgian, M9 is Italian, M320 is German, and CG is Swedish… these are all countries known for not being THE GODDAMN COMMUNISTS Y’ALL’VE BEEN FIGHTING SINCE WW2!

            You see the issue politically speaking.

      • int19h

        Can you expand on those reasons?

        • For a start, the preference in the US is for disintegrating belt links, which are not compatible with the PK. The Polish UKM-2000 does use M13 links, and is based on the PKM, but it uses a completely different Western-style feed mechanism and pawl. Also, the barrel is shorter because the chamber was moved forward to accommodate the same ejection pattern as the PKM with the new feed path.

          Perhaps a PKM-style weapon that is compatible with Western mounts, etc. could be developed in concert with a new closed loop disintegrating belt link design (similar to that of the M2 machine gun), but no such weapon exists off the shelf.

          Also, the M240 is considered broadly satisfactory for the GPMG role. It is more durable and reliable than the PKM, although heavier. For the Marine Corps, I do not think this additional weight is a problem due to the way machine gun teams are organized. For the Army, it is, but I think the PKM is only seen as superior in the dismount role, not in the GPMG role as a whole. Therefore, the impetus was to lighten the M240, rather than adopt an entirely new weapon.

          • Kyle

            And of course the Army, being jealous of the Chair Force, choose the most expensive lightweight replacement because the taxpayers can suck it.

      • Ark

        Just sayin’, if their jimmies are getting all rustled over the thought of Talibs with PKMs outranging them in the mountains of Afghanistan…

    • James O Donnell

      Because the FN MAG-58/M240 is as good if not better?

      • int19h

        How is it better?

        PKM: 16.5 lbs
        M240: 25.5 lbs

        What metric do you claim M240 is better on, that it justifies a weight difference of 9 pounds? This is almost 200 extra rounds of ammo that could be carried.

        • James O Donnell

          PKMs have a shorter service life than the 240. Lighter is rarely better when dealing with a GPMG. The M240 is compatible with day, night and thermal optics, while the basic PKM is not (adding that capability increases the weight several pounts).

          Having used both, I will take the 240 and let my AG and AB worry about carrying the ammo.

          • jono102

            The 7.62R belt also takes up more space than the same amount of 7.62 NATO belt. The design of its link belt spaces the rounds out more, notice the difference in size between the 100rd box on a PKM vs the one on the 7.62 Minimi.

          • iksnilol

            So?

            It’s still lighter. You can still carry more ammo with a PKM than a M240.

          • int19h

            I don’t see how adding a rail could possibly increase the weight by several pounds, even if it has to be side-mounted.

            Shorter service life – what are the numbers, exactly? I’m not aware of any PKM or Pecheneg users complaining about service life. This would seem to imply that even if it’s shorter, it’s still “good enough”.

            As far as weight – for vehicle-mounted guns it doesn’t matter much. But I don’t see how it could possibly not matter when you’re humping it. It doesn’t matter if you have another guy to carry the ammo or not – ultimately you’re still carrying several extra pounds of weight between you two, which could be used for ammo instead.

          • micmac80

            PKM aftermarket mount doesn’t weigh much at 320g so way under a pound factory fitted ones even less. How did you get to shorter service life? Barrels are consumables and barrel life depends also of ammo.

            In any case 99,999% of the time you are hauling the piece around so weight matters a lot.

          • Renato H M de Oliveira

            Barrels aren’t the only parts that have service lives.
            In some MGs they weren’t even the most worrying ones (looking at you, M60).
            That said, both are fine guns, with their own limitations.

          • Sermon 7.62
      • roguetechie

        No, not even on it’s best day when going up against pkm’s thousands of rounds past their technical service lives…

        If you don’t know EXACTLY the incident I’m referring to you don’t know enough to be nearly so smug smarmy and certain about ANYTHING regarding machine guns…

        Much less this specific thing where you’re wrong, wrong, wrong, and oh did I mention WRONG

        • jono102

          How do you quantify such an opinion? Is it from personal in depth experience with both machine guns or commanding soldiers using them? In what role are you referring to, light, GPMG SFMG, by day or night? In the hands of a trained soldier, conscript or otherwise?

          They are both good machine guns with their individual strengths and weaknesses. Its who you intend to use them and how that decides which one suits best.

          • roguetechie

            Actually, it’s not an opinion…

            It’s a statement / series of statements based in PILES of real world data like DOD reports etc, my own personal experience building and working on various belt fed guns, my extensive reading and research into all things machine gun, my conversations with and informal one on one and group range tactical & practical instruction received from a number of veterans…

            And, you know, some other stuff here and there …

        • James O Donnell

          And the evidence, besides your foot-stamping and widdle-fisties waving?

      • iksnilol

        PKM is much lighter, and at worst just as accurate and reliable. At best, more accurate and reliable.

        Thus, logically, PKM is better.

    • Ryfyle

      I’m down for it.

  • Anomanom

    Firing deep-frozen rounds fed from a dewar flask. I wonder if that helps keep the heat down during extended fire.

    And does it add an ice damage type to the bullets?

    • micmac80

      Cold makes many plastics brittle and they are probably trying to showcase that links did not start breaking apart

      • Anomanom

        I’m sure that was the point of doing it. I just wondered whether the bullets being cold has a noticeable effect on reducing heat on the barrel. The ice damage was purely a gamer joke.

    • Ryfyle

      Like a 1d3 Ice Damage at 20m.

  • James O Donnell

    Meh… A disintegrating metallic pull-out link has been used on the Browning M1917/M1919 guns since the 1940s…

    The Soviets/etc stuck with non-disintegrating belts for decades because they were cheap bastards who placed a high value on belts that could be reused, over disintegrating links that would not get tangled up in vegetation, vehicles, etc. Basically, being able to reuse belts was as important as sending soldiers home life and unmaimed.

    A disintegrating link is a long-overdue step forward for the PK-series guns, But a plastic link may be a step too far forward… The weight savings over a simple Browning-style link should be minimal, and a metallic link would have far less chance of issues, especially at temperature extremes.

    • SP mclaughlin

      Don’t let the slavaboos here this.

      • jono102

        You mean, “Don’t let Sermon hear this”, surprised to have a PKM or Russian based thread and he not posted in it yet.

        • KestrelBike

          He did not disappoint lol. (I liked his well thought out comment, actually)

          • ostiariusalpha

            More like a semi-coherent amalgam of his usual biased defensiveness with a couple sound points, but its a step up for him.

      • iksnilol

        DAVAI DAVAI!

    • Sermon 7.62

      There is a common misunderstanding that implies a kind of Russophobic assertion engineered in the basements of the Pentagon that the Russians consider their soldiers expendable. That’s bullcrap.

      For example, there is a line of reasoning such as the Russians put brakes on their AK instead of flash hiders to ensure that a soldier could shoot in bursts, running fast in order to get close to the adversaries. In contrast to that, the NATO uses flash hiders and not brakes in order to help soldiers to not expose themselves and that’s because in the NATO armies the life of a soldier is considered a higher value, than the life of a soldier is for the commies.

      In truth, the reason for that is the fact that it is much easier to hit a target shooting in bursts and thus a brake is better than a flash hider because to survive in a combat a soldier has to kill his opponents first.

      The same is here. Most people haven’t heard about it, but the Russians had polymer frames for PM pistols in the late 60’s and rejected them since it was determined that such a frame was not going to endure well in the long term.

      Instead of making cheap crap like the bastards in the NATO, who think about people in terms of numbers and trade, considering a war being nothing else but a business enterprise, and making unreliable disposable magazines in Russia things are made to last.

      • mosinman

        your comment was good up until the final paragraph where you went full Sputnik news.

      • roguetechie

        LOL Sermon man you did so good until you went left there at the end…

        Speaking as someone who owns both AR’s and AK’s in 5.45 and 5.56 there’s an even more basic reasoning behind the two choices.

        Simply put, 5.45 doesn’t deafen you and slap your squadmates stupid when you fire in enclosed spaces or close proximity to each other.

        5.56 OTOH, does

      • Ryfyle

        From what I’ve seen. it’s more of a case of 50 non disintegrating belts liked up through tabs building up to 200 rounds. Personally, I would cut it down to ten 20 round belts if snag-age was such an issue.

      • James O Donnell

        Probably based on the observed reality of Russian profligacy with their lives of their soldiers time and time again.

        Polymer seems to have worked just fine for Glock. Maybe the Soviets should have stolen better plastics from the capitalist West?

  • LazyReader

    Polymer, its a fancy word for plastic

  • James O Donnell

    Your silliness isn’t worth addressing. Back to mom’s basement and Call of Duty with you.