Posted on 07/02/2021 4:39:49 AM PDT by MikeSteelBe
For a while now, photos of a very unusual AK-style rifle using an AR gas system have been making the rounds on social media sites, and we now know it’s real, courtesy of Polenar Tactical. A prototype design by Tinck Arms, the rifle doesn’t use a true direct impingement gas system, but a hybrid system using a remote short-stroke gas piston.
What Tinck Arms achieved with the combined gas systems is a free-floating barrel, to make an AK shoot without the characteristic barrel whip. And because the piston system is separated from the bolt carrier, it also produces noticeably reduced recoil.
Tinck Arms is a Slovenian company that some may recognize as the developers of the Perun family of firearms. The Perun is a modular platform loosely based on the AR-15 that uses proprietary self-contained upper receivers.
This modified AK is built on a Zastava M70 receiver, and it mostly uses AK components. It also has a large, modular handguard with M-Lok slots and an extended rail section for optics and accessories. The top rail continues back over the rear trunnion to place an optic closer to the rear without interfering with the dust cover.
With the handguard removed, it’s immediately obvious that this prototype is different. Instead of a large AK gas block and piston tube, the rifle has a typical low-profile AR gas block and standard AR gas tube.
Hopefully accuracy tests will come soon since that is the primary benefit of this system. (Photo: Polenar) The gas tube runs from the AR gas block to a secondary gas block at the barrel trunnion. The system uses two gas blocks, one to tap the barrel and the other to run the gun’s short-stroke piston system. The handguard and rail mount to the secondary gas block and the gap between the front trunnion and receiver.
The short-stroke piston completely replaces the long-stroke piston and doubles as a guide rod for the bolt carrier and action spring or recoil spring. There only look to be a small number of changes to the AK parts, and nothing that looks like it would be considered too permanent.
Aside from the cut-down bolt carrier and maybe a replacement trunnion for the AR-style barrel, the rest of the AK looks unchanged. Even the bolt is a standard AK bolt, although it’s hard to tell at a glance how the bolt, trunnion and barrel interface. However Tinck did it, it clearly works.
Excellent video that thoroughly covers the pros and cons of the hybrid design - as opposed to the typical marketing videos.
Love the Adidas track suit jacket.
Not sure what they mean by "barrel whip" - if they're talking about the large inertia imparted by the bolt/bolt carrier/piston of the AK - OK, makes sense but it's an odd term for what's going on.
It's not actually "free floating" the barrel - there's still the gas block and tube hanging there - a short-stroke piston assembly would have an almost identical effect on barrel movment.
Excellent vid and he does a great job of explaining how it operates.
He was putting the safety on when he was moving, between shots. I’ve never seen this before. Is it a common practice for shooting the AK?
By the way, I want one.
What is wrong with the time and trial proven default and reliable AK system? Is this fixing something that is not broken? Why add more parts than actually needed to anything let alone a firearm? Is that long thinner gas delivery tube going to plug up faster?
I see a whole lot of “Why” in this concept.
“but not sure that remoting the piston with a gas tube is a great idea”
The AK system wasn’t broken. It’s probably the most reliable semi auto rifle ever invented so I don’t understand why they did this.
This, however, is an idea whose time has come:
L
ArmaLite's primary intent, when they incorporated the DI gas system, was likely weight reduction - something that is evident elsewhere in their early AR10/AR15 designs (not to mention the company's name ;^)...
You're right about the basic AK design: the most reliable weapon system in history. Luckily for us, short stock, coarse sights, short sight radius, and the first position in the safety is full-auto which gives us some relief if the first round doesn't hit you.
Like the RPG, no idea why we didn't just copy the damn thing and improve it for our use - instead of sticking with Matty Mattel.
Something like that was attempted - the Gwinn Bushmaster...
In slow motion video, you can see the barrel movement on an AK. It kind of looks like a whipping motion. I agree with all of your comments.
They are trying to make the AK system more accurate. The long thin tube on the AR system does not plug up.
The difference in accuracy is the round not the action. The 5.56 is just naturally more accurate than the 7.62x39. And we can already buy AK47 platforms in 5.56. No need to redesign the firearm at all.
I agree... and holy AK50 cow! :)
When I was involved with artillery design, we used very high speed video to watch all of the motion of the weapon and it was disconcerting to watch what you designed as a solid steel and a more or less rigid system, move around like Jello during the firing.
Definitely makes one less confident while standing next to the dang thing!
Brandon Herrera’s AK-50 prototype project is very interesting, but I don’t think that I would ever fire anything like this. Especially after what happened to Scott at Kentucky Ballistics while using a Barrett.
True, he was using questionable 50 cal ammo, but if something like this can happen with a tried and true Barrett bolt action then I don’t think I could ever trust a 50 cal semi in my hands.
The AK has more mass moving than the AR. I like the fact that they are trying to get the best of both in a new hybrid design.
And that more mass is why they “whip” more. I hope it works out for them. But I will stick with my SKS over either.
Some bolt actions are incredibly strong. Frank de Haas wrote about a case, where a customer brought a .30-06 Arisaka 'sporter' to his gunsmith, complaining about excessive recoil. Turned out, it was a 6.5mm (NOT 7.7) Arisaka, that had been rechambered - but not rebored - to .30-06. So everytime he fired it, the owner was swaging a 0.308" projectile down to about 0.264" - no wonder the recoil was a bit much.
But no matter how strong the action, enough propellant (or explosives, or stupidity) is likely to result in structural failure...
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