Picked up a WASR-2 at cost to mess with, but instead its messing with me

I bought it from a dealer who told me it was having problems and i thought i could figure it out, but i am baffled. Should'nt be really considering its from Century.
I've fired around 30-40 rounds thrugh it so far like a bolt action rifle. I can cylce the rounds by hand and everthing is smooth, but when firing they somethime eject by hand ok, and others require a good bit of elbow power. The bolt will come back about 1/4 -1/3 of the way. judging by the carbon on the piston, it is getting some gas. I ran a pipe cleaner and a bent paper clip and could see the clip protrude from the hole into the barrel, but i wonder if the hole is not properly aligned or right size? The bolt seems fine and i have tried three differnet lots of 5.45 (all wolf though) as well as using different mags. The rounds of course will expand after fired, but one of them cracked down the neck very cleanly. I dont know if happened while discharging or if it occured when the action tried to cylce but pushed it back into the chamber.
Eliminated:
-ammo
-mags
Possible problem:
-gas block
-head spacing
-gas piston
Variable:
-recoil spring
-bolt/extractor
I'm sure a gunsmith could fix it, but wanted to eliminate anything that might be simple. If its the head spacing, then im worried. The recoil spring does not feel to strong/weak compared to other recoil springs. The extractor in the bolt seems "fine" but im used to 7.62mm AK's.