Loose AK gas piston?

Jl89

Private
Minuteman
Sep 10, 2019
5
2
Long story short. I’m putting a KNS piston on a PSA 103. Piston pin would not want to come out no matter how hard I hammered. Post install, the pin looked suspicious, the rivet looked deformed on the backend and the piston had zero wobble. Like someone installed it with a sledge hammer. Ended up drilling out the pin with 1/8 cobalt bit all the way through. Piston unscrewed easily. Installed KNS with included roll pin. Feels good with a slight wobble. Only Concern is that the roll pins are slightly smaller than the 1/8” holes in the carrier. Idk tho because I measured what was left of the rivet and it is 1/8”. But the new roll pin is super snug in the piston itself tho. Here’s some pics, it’s super marred from me trying less invasive measures such as filing the rivet head off but it is what it is.
Would you say this piston is good to go? Thanks!!!!
 

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Pull it back apart and make sure both ends are square. You could have damaged it during disassembly. What made you change it out?
 
It is a KNS adjustable gas piston, I put it in so I can run it supressed. I checked and the net piston seems ok, it’s just that the provided roll pins are slightly smaller that the holes in the carrier 🤔
 
I I mite have found the answer to
My own question, step 8 from the instructions say the pin may be loose in the carrier and the threads take all of the force. I’m 🧑🏼‍🦯
 

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So my problem is similar but different: after much swearing and cursing I was able to knock out the pin and unscrew the piston, but now the new piston holes don’t line up well with the holes in the carrier. In the instructions it says to tighten it all the way down, then back it off till the holes line up; doing that however leaves a pretty significant gap between the shoulders of the carrier and the piston. If I could find a washer to fill the gap that would be perfect, but I don’t think that‘s going to happen...in the meantime I’m very concerned about the threads taking all the force of the blowback and reset on each shot fired
 
So my problem is similar but different: after much swearing and cursing I was able to knock out the pin and unscrew the piston, but now the new piston holes don’t line up well with the holes in the carrier. In the instructions it says to tighten it all the way down, then back it off till the holes line up; doing that however leaves a pretty significant gap between the shoulders of the carrier and the piston. If I could find a washer to fill the gap that would be perfect, but I don’t think that‘s going to happen...in the meantime I’m very concerned about the threads taking all the force of the blowback and reset on each shot fired

i had a similar issue. It would not screw it all the day down. it took 30 minutes of wrenching to rework the new threads. Works fine now. I bought the kns to be able to make the rifle smoother shooting, but it was not reliable for that use, so i tune it almost to the bottom.

sure it helps for the suppressor though.
 
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