HELP WITH NEW SKS...

HI are there any sks gurus here? New to sks, have several ak"s, i got a yugo model 59 sks recently at gunshow. Took it to range to try it out. It cycled roun d an fired fine, but didnt cycle but about 1/2 way. So round didnt eject, cycled it manually and fired 20 rds. All did same thing, had to manually eject each casing. Would this be a weak spring or gas piston? Any help would be greratly thanked

Is it the M59 or the M59/66?

The 59/66 has the grenade launcher.

Either one needs to have ALL the cosmo cleaned out of everything.

Complete diassembly and cleaning of everything.

It could be sticking up from cosmo?

Not uncommon problem.

It could also be an issue with the gas bypass valve for the launcher if there is one on that rifle.

thanks, it is a 59 no grenade launcher

cleaned it and punched barrel b4 shooting it, but didnt check gas return pipe

See if theres cosmo in the gasport and if it improves after cleaning?

I'd say something with the gas system like Black-Wolf. I've seen SKS's sold with the gas piston missing! Check out the entire gas system including the gas piston extension and spring located under the front sight. To remove the gas piston extension, after removing the hand guard, Raise the hand guard latch fully upward, but be prepared for the piston to launch because it is under pressure. I keep a brass rod handy to hold the piston while raising the latch. Also check the gas port (hole) located in the gas cylinder front bracket. I usually clean the port out with a pipe cleaner soaked in solvent.
Like Wolf said, it may be packed full of goopy cosmoline. Hope you get her running!

What ammunition? If it's the German training ammo it won't cycle.

thanks for help. It wuz fouled gasport, cleaned it out , works like new.

Thanks again

Good deal.