WK-180 Piston Rods

Is there anything current WK owners can do to try to mitigate or reduce the chance of failure? Or is this a flawed design issue that will come up again and again. I know that one of our vendors came up with a beefier charging handle to address the reported shearing off of the OEM one.

I ask about the age of the WK, because I read reports of piston and charging handle failure from a couple of years back. I am surprised if Kodiak has not retrofitted/re-engineered failing parts that have been reported more than a few times. Seems like just replacing it with the same parts is going to just buy time until the next failure.
 
I see…very interesting. Hence why I’m a big fan of middy gas guns, but…being a piston gun, isn’t excess gas bled off rapidly once the piston clears the valve holes?

Obviously if the rifle is over gassed, ie, the barrel port is too big, we will end up with accelerated parts wear, however…snapping pistons in a few hundred rounds? Is it that simple of a solution? If so, great! But that seems too easy…no?

Thanks for all the input, please don’t stop, let’s figure this out.
 
thegazelle said:
Is there anything current WK owners can do to try to mitigate or reduce the chance of failure? Or is this a flawed design issue that will come up again and again. I know that one of our vendors came up with a beefier charging handle to address the reported shearing off of the OEM one.

I ask about the age of the WK, because I read reports of piston and charging handle failure from a couple of years back. I am surprised if Kodiak has not retrofitted/re-engineered failing parts that have been reported more than a few times. Seems like just replacing it with the same parts is going to just buy time until the next failure.
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It does feel that way, doesn’t it? I know where your coming from.

But, as I explained earlier, I do have some degree of sympathy for Kodiak when it comes to these issues. Let’s take the cocking handle for example…so of you market an ‘improvement’ that kinda suggests your last offering was inferior by definition. And then the phone starts ringing off the hook with people demanding a warranty ‘upgrade’. Not defending Kodiak, I have zero connection with them, other than a few very honest phone conversations with a very genuine sounding gent who I have no reason (as of yet) to not believe is trying his best to put out a satisfactory product for a reasonable price.

Who remembers building AR’s in the 90’s? Before the TDP was common knowledge? Franken guns and junk parts, I’ll admit, I’m an AR snob (or I was until princess twinkle socks screwed us) but it wasn’t that long ago we came together as a community to solve these problems, how about we do that again?

This is why I started this thread, as opposed to getting just another replacement piston from Kodiak. Ok, they got us here, let’s take it from there and see what we can do. This forum is full of knowledge and experience, not to mention site sponsors with manufacturing capability…
 
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ColinD said:
I’d be curious to know how the barrels that ATRS are making for the platform are preforming. I know those guys are sizing the gas port much smaller than factory, and they know what they’re doing when it comes to barrel making.

Like others have said, there is likely several factors contributing to the snapped rods, but maybe solving the over gassing would keep the rod from experiencing stress it can’t handle. That being said, the adjustable gas block might do the trick as well with a lower price tag.

I have a metal lathe at home, if I had time I would try and make one out of tool steel or something. I haven’t had my rod break (ws-mcr) I’m not sure if the two manufacturers are using different materials or not.
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That’s very interesting, thanks for your insight. I would also be willing to re-barrel if it’s as simple as that, but as you eluded, maybe it’s the metallurgy or heat treat of the rods? Or a little of both?
 
Not the solution you want to hear, but what about boxing it up and shipping it to Kodiak. Would they not make it right?

Cheers
Moe
 
Thank you for your suggestion, but I don’t think that will solve the problem. I’ve had nothing but great experience with warranty and customer service from Kodiak, but, unfortunately, it seems some of these chronic problems will have to be solved in the aftermarket.

How many WK’s are there out in the wild? No numbers, obviously, most are in Canmore on canoe trips I hear tell, but isn’t there a substantial market for high quality upgrades, no? Am I being naive? I’m not a machinist or fabricator, so I’m feeling around in the dark.
 
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The Jard J180 build kit is coming in late July from Sylvestre Sporting Goods, assuming it doesn't get delayed again. It uses a gas tube to directly impinge the bolt carrier group against an AR-180 style recoil recovery system instead of a piston. Although this may introduce other issues, it does eliminate the piston as a point if failure, and allows use of lower profile handguards and barrels with any length of gas port.
 
Interesting…I’m intrigued I’ll admit, but also I feel old ha ha…

Remember when AR piston conversions was the hottest thing in town? Then all the carrier tilt issues, bolt lugs shearing, buffer tubes were getting chewed up, all to make a DI gun run piston…

Does anyone else see the irony in now we are trying to make a piston gun run DI? But thanks for your input, I will fully support any company that chooses to improve any firearms platform we still have access to in Kanada.
 
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Rfn said:
Thank you for your response Sir, you bring up a good point. Is the gun over gassed? Perhaps. But, an adjustable gas block will regulate gas within an acceptable level, IE, the gun is ‘dirty’ or inclement environments. But it shouldn’t snap rods.

So….?
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gas imparts a force onto the rod, rod accelerates, gas bleeds off once rod travels a certain distance. regardless of the bleed-off, force and acceleration still transferred to the rod. with an adjustable gas block you reduce gas before it gets to the rod, so less force, less acceleration, rod doesn't impact bolt as aggressively, etc.. with less force presume lass damage.

edit to add - kodiak probably tried to reduce the force imparted with a heaver spring on the piston, but in this case instead of reducing force they are setting forces against each other with the rod as the moderator. with the spring involved you may get shear forces on the rod which is not the best.
 
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So on the same WK, I’ve had a piston snap and a bolt lug sheer off.

The weapon itself is good, I liked it and I liked the performance however this is the only firearm I’ve ever seen sheer a bolt lug. Round count was relatively low as well.

I will say for the record Kodiak has the best warranty service from I’ve experienced in my life. They should be proud of that and proud of their rifle. It’s a fresh design for them so I’m not holding any of these problems against them. Look how many iterations of AR and AK it took to get where we are with that.

Would one of the other similar platforms have a piston that could be swapped in perhaps? I’m not familiar enough with all these new 180 versions to know.
 
Rfn said:
This is why I started this thread, as opposed to getting just another replacement piston from Kodiak. Ok, they got us here, let’s take it from there and see what we can do. This forum is full of knowledge and experience, not to mention site sponsors with manufacturing capability…
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Agree with you completely. The reason I asked that question as well is that I haven't received a direct answer from Kodiak whether they have made any changes to that rod or handle in recent shipments. All they told me is that there are 11,000 WKs out there, and these failures represent a very low percentage of the units. And if there is a problem, we can send it to them. I am not sure what the warranty is on these (I will look it up later) but if the replacement part is the same, there will come a time where if it keeps getting replaced under warranty, the warranty will run out and what then?

Maybe I am naive to think that companies will change a proven failed part. I have a German car, and it is a known fact that the electric water pump in these models for the generation that I have is guaranteed to fail. Not may fail, but will fail (it's just a matter of when). I reached out to the company to ask about the replacement water pump, and shockingly, what they will put in is the same one. They never re-engineered it. So between 40,000 and 150,000 km, it will fail again.

If you look at some other guns like JR Carbine, FX9, TNW ASR, earlier versions of those have had known failures with certain parts - over time, they have changed / improved the parts - I am hoping WK did that (I bought mine earlier this year as well), but I haven't confirmed this yet. I agree that aftermarket may be the way to address this - TNA I think developed a bolt lock/release for this, and another company developed the better charging handle (think it may have been Spectre, but if it's not, correct me)...

Someone could make the argument, however, that it should not be incumbent to have third party vendors fix a problem that the OEM should be actively addressing.
 
I agree 100 percent. But I’m impatient and not going to hold my breath for Kodiak to shoot them selves in the foot by publicly admitting any design or material shortcomings. I’d rather spend some money and support aftermarket manufacturers and deal with the issues now, rather than later.

I just want this thing to work.

As to the gas port, I was surprised by how large the factory port is. I compared it to a stripped 14.5” BCM barrel (carbine gas) I had laying around, and the difference was substantial, but I assumed that would be the norm for a piston gun? I don’t have anything I can compare it to.
 
Can you post some close ups of the broken bits, specifically showing the broken face(s) of the metal? for metal to break like that from compression typically indicates deflection or excessive impact. how much end play do these rifles have on the piston rod when the bolt is locked? will the carrier "tilt" on its guide rails?
 
Yes, better pics of the face of the breakage !
If its a problem with heat treatment… the fracture can tell you alot !
If the face has a very coarse sandy appearance then the grain structure maybe be very large…. Large grain = brittle

Even metal coming from the supplier can be problematic
 
Crusader said:
I went with a mid length gas system. Yeah I needed to buy a new barrel and piston but I don't seem to have these problems.
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KAC or Armalite? Who's barrel and who's piston?

I'm interested in hearing more on these mods and following TNA's release of aftermarket support.
If I'm liking what I see, I just may jump back into one of these.
 
Any possible way to use a two part piston as in the SKS design. Some type of block to add at receiver face and house the stub piston and spring then the longer piston up front. May be able to shorten the original and only need the block with short rod/spring ? Again something for someone with design/machining abilities.
 
beltfed said:
KAC or Armalite? Who's barrel and who's piston?

I'm interested in hearing more on these mods and following TNA's release of aftermarket support.
If I'm liking what I see, I just may jump back into one of these.
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Nothing so fancy.

A NEA 18.5" barrel and a Third Echelon Design gas piston.

I used a number drill bit to dimple the bottom of the barrel where one of the grub screws sit so it bites into something (like the manufacturer suggests) and does not allow the gas block to rotate.
 
Crusader said:
Nothing so fancy.

A NEA 18.5" barrel and a Third Echelon Design gas piston.

I used a number drill bit to dimple the bottom of the barrel where one of the grub screws sit so it bites into something (like the manufacturer suggests) and does not allow the gas block to rotate.
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I stumbled across these guys in my barrel searching. They have mid length op rods which allow a wider range of barrels to be fitted.

http s://thirdechelon.ca/index.htm

Actually it might have been Crusader who turned me on to them!
 
^
Nice, that op rod would pair nicely with the TNA adjustable gas block, and allow a much greater variety of donor barrels in builds from parted out now prohibited firearms.

They also have a right side charging handle channel cover, and a cool 3D printed WK charging handle that is a unique design.
 
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