SKS not cycling

[dowork1021 64]

i have an sks that i bought and it wont cycle. its the yugo version and i have the grenade launcher swith turned to rifle mode(im not that new). so i purchased a new gas port regulater hoping that it would fix my problem but it didnt. could there be a leak in the gas tube or something? i need help!

[Casp 119]

You're far from being the only person who's had this problem. The Yugo SKS's have a little bit of a reputation for having a leaky gas block. Sadly, off the top of my head I don't remember how to fix it, but I'll do some digging real quick and let you know.

[dowork1021 64]

yes please do. it would be a big help. thank you.

 

 

[Casp 119]

A temporary fix I've seen a few people do is form a washer of sorts out of a paperclip and stick it between the gas valve and the end of the cylinder to take up the gap; it makes the gun run but doesn't last very long. That's what I was thinking originally, but I wanted to look around and double check since it's been a few years and my memory likes to play tricks on me.

 

You say you got a replacement valve and that didn't fix the problem? Was it the one from CNC Warrior? That's the only thing that comes to mind. you can try wrapping paper around the gas cylinder and block to see if it shows a leak anywhere (propellant gas leaking from anywhere on the gun should leave pretty obvious burns on the paper,) but a leak in the cylinder itself seems pretty unlikely.

 

Edited for my own stupidity and not re-reading the OP

Edited March 21, 2011 by Caspian Sea Monster

[Casp 119]

(Still brainstorming)

 

In terms of diagnosing the problem, the only things that should cause an autoloader to shortstroke are:

 

• Insufficient gas (not enough pressure, not enough dwell time, blocked port, gas leak, underpowered ammunition, undersized bullets)
  
• Moving mass (bolt/carrier group) too heavy
  
• Recoil spring too powerful
  
• Too much binding friction on moving parts (filthy, no lube)
  

Gas dwell time, bolt group weight and spring power can all be pretty safely ruled out on a stock SKS, and I assume the gun is clean and oiled. Have you tried different ammunition? Only other thing I can think of is the possibility that the new gas regulator you bought is just as out of spec as the old one.

 

.......it's about 2am, I should probably sleep.

Edited March 21, 2011 by Caspian Sea Monster

[dowork1021 64]

Yes i bought it from cnc warrior. the new one fit in there tight, real tight. ill try what you said about the paper. i have been using herters ammo witch runs flawless in my mak 90.

[DrThunder88 912]

If you haven't already, I'd give the gas port and gas tube a good cleaning.

[Kliegl 304]

Is it moving the bolt AT ALL? If not, I think it's stuck on nade mode.

[dowork1021 64]

I re-blued the whole gun before i had even shot it so it was squeaky clean with fresh oil. I think its leaking where the gas tube meets the gas regulator. Has anybody heard of the tube being the problem? Also the spring in the rear sight block that conects the gas piston to the bolt carrier seems really stiff. Much more than my ak's recoil springs. But its a factory spring as far as i know. It cycles completely 1 time in about 20 rounds or so but all the other times it only travels back about an inch.