cycling problem with my SKS

[klalewicz]

I've got a YUGO model SKS that cycles just fine for the first 10 shots or so, then it seems like once the barrel and gas tube are heated up, the piston isn't able to fully cycle the bolt back to eject the brass. Any suggestions?

 

[Aunt Bee]

The coefficient of expansion of the gas tube metal is prob greater than the COE of the gas piston when heated leaving a space. -- Also, does the top edge of the piston show any slight corrosion?

 

[railroader]

If your gun has been cleaned thoroughly of cosmoline then it sounds like a gas leak. Here are new gas valves. http://www.cncwarrior.com/comersus/store/comersus_viewItem.asp?idProduct=1 Mark

 

[rockit]

Is it clean, including the gas system and port?
Is the recoil spring inserted correctly?
Have you tried different ammo to rule that out?