Zlatmash KSO 9 Krechet 9mm Carbine

Zlatoust Machine Building debuted their new KSO-9 “Krechet” semi-automatic carbine recently at the Moscow 2013 Arms and Hunting Show. Based off the Russian Kedr submachine gun, it’s chambered in 9x19mm and features a Picatinny quad-rail, a compensated barrel and CAA Tactical polymer furniture. It wasn’t specified which it will come with, but both 10 and 20 round magazines will be available.

Ray I.

Long time gun enthusiast, archery noob, Mazda fan, Sci-Fi nerd, Whiskey drinker, online marketer and blogger. My daily firearms musings can be found over at my gun blog ArmoryBlog.com and Instagram.

Shoot me an email at ray.i@staff.thefirearmblog.com


  • wetcorps

    The muzzle device looks like the internals of a silencer.

    • mechamaster

      Maybe it’s work like AN-94 muzzle device.

    • bbmg

      Definitely resembles the baffles on the PB suppressed pistol:


      Possibly like the SIG MPX-C a tube can be added to convert the brake into a suppressor: http://www.sigsauer.com/CatalogProductDetails/sig-mpx-c.aspx

      Given the dingle baffle, diminutive nature of the tube and supersonic velocity of 9mm from a long barrel, I doubt it would be very effective though

      • Diagram of the entire PB pistol, from 1982-dated Soviet army manual.

        • DiverEngrSL17K

          Another informative post — thanks!

      • wd

        147gr are subsonic out of a 16″+ barrel.

      • DiverEngrSL17K

        Nice post — thanks!

  • Lance

    Seen something similar for sale here already. Looks like another Pistol Caliber Carbine. Yawn I want a Bison semi auto and to see some of those PB pistols here that be a lot more interesting than a AR look alike PCC.

  • BOB

    Nice… compensator. Took a page from Sig’s book now did we?

  • BillyBadfish

    It doesn’t seem uncommon now to see new Russian firearms released with CAA Tactical furniture.

    • noob

      is it because Magpul won’t sell to russia due to their self imposed interpretation of ITAR?

  • DiverEngrSL17K

    Different, and intriguing. A more in-depth, follow-up technical evaluation would be interesting as the KSO-9 becomes more available. Until then, we can only speculate.

  • Alex Nicolin

    Do you get any advantage from having such a long barrel? I think 9 mm velocity flattens out pretty fast, at 8-10″, so there’s no need to make the barrel longer than that..

    • bbmg
    • Alex Nicolin

      Yes, I see there are indeed increases, but very small ones. What is surprising is that the velocity seems to be going up and down slightly, as the barrel gets longer. I have no idea why.

      • loopydupe

        -The gas pressure behind the bullet being lower than the pressure in front of the bullet is what propels the bullet.
        -The gas pressure behind the bullet increases as the powder burns, but there’s a limited amount of powder.
        -The gas pressure behind the bullet decreases as the volume inside the barrel and behind the bullet increases due to the bullet having moved forward
        -Friction between the rifling and bullet decelerates the bullet.

        So at a certain point, the volume inside the barrel behind the bullet has increased enough so that the pressure pushing the bullet forward is weaker than the friction slowing the bullet down.
        Pistol rounds are loaded with faster burning powder than rifle rounds, since pistol rounds are designed for use in shorter barrels than rifles. So that’s why this inefficiency happens when you give a pistol round a rifle length barrel. It could also happen with a rifle round, but only with an absurdly long barrel.

        Going even further, the pressure behind the bullet can get even lower than the atmosphere, so pressure forces would also start to slow the bullet. If I remember correctly, this is why an M79 makes its distinctive sound. After the grenade gets out of the way, rather than a muzzle blast, the reverse happens; air gets sucked into the barrel.

        A squib load takes this to the extreme; friction can completely stop a bullet, leaving it lodged in the barrel, if the round was made with extremely low propellant, such as a primer only. This can cause disaster when you fire another round. If you fire another regular round, the gun can blow up and injure the shooter. If you fire a blank, you can fire a bullet when you didn’t expect to, which is the error that killed Bruce Lee’s son.

        • Alex Nicolin

          Yes, this makes sense, and is what should be expected – the velocity increase tappers of as the gas pressure behind the bullet decreases. But that’s not what is shown in the experimental data on Ballistics by the Inch. Instead, quite surprisingly, the velocity increases steadily to a point, then decreases and increases again a few times, before it stabilizes. From a point on accelerates, that decelerates, then accelerates again in a few cycles. I have a hypotheses about this: the powder does not burn steadily in the tube, but in fact a large portion of it gets compacted and stuck to the back of the bullet, and flares in fits and starts. In fact, if high-speed frames of handguns being fired show a large cloud of unburnt, and unignited powder particles being blown from the muzzle, together with the bullet. http://kuulapaa.com/home/highspeed/pistols.html

          The only way they could have failed to ignite is to have stuck together tightly so only the surface layer of this mass of powder burned. The “plug” of powder is more pronounced in pistol cartridges, because they don’t have shoulders to keep the powder burning in the tube. Rifle cartridges with steeper and wider shoulders (those who are short and fat) keep a larger percentage of the powder burning in the tube, since the plug diameter is minimized. There were some guys at a site called superior ballistics that thoroughly studied the phenomenon of “plugging” powder, but unfortunately, the site is dead.

          • loopydupe

            Ah, I misunderstood you. I took “up and then down” literally, instead of seeing that you meant it was a pulsating sort of thing.

            Yeah, that phenomenon is strange.

            Your theory as to what’s happening is very interesting, let me see if I’m following correctly.
            So you think the back portion of the powder actually burns, and the pressure from that compresses the front portion of the powder up against the back of the bullet too tightly, and so instead of the surface of the powder particles burning, only the surface of the compressed clump is burning? And then when the pressure lets off, the clump breaks up a bit, since it’s less compressed, and that loosened powder that comes off burns quickly again, bringing the pressure up and accelerating the bullet once more?

            That’s a very neat mechanic, if that’s what’s going on.
            Bullets on cruise control.

  • Vernon682

    Am I the only 1 who thinks this gun looks awesome?