View Full Version : Yugo Underfolder build... won't cycle

March 9, 2009, 02:15 PM
Hi Guys,

I don't post much, but have been a member for a while, and read quite a bit. I am in possession of a Yugo underfolder built on a global trades receiver. My brother acquired the kit, and got disgusted with it because he feels it is too loose (upper and lower hand guard wiggle a bit, dust cover wiggles a bit, is all I can really tell)... Anyway, the main problem with the weapon is that it wont' fully cycle after the first two or three rounds out of a mag... any mag I have tried.

I have a romanian build that functions flawlessly with any of the mags I have tried, although it was an unissued kit, the yugo is "broken in"

Anyway, have tried different ammo, different mags, but past that point, I don't know where to start. With the price of AK's going up, if I can get this one to work, it would be a good value to me :). My brother was going to demill it and use it for parts, but told me I could keep it if I could get it to cycle properly through one 30 round mag.... :mrgreen:

Thanks for any suggestions,:confused:


March 9, 2009, 11:09 PM
Any suggestions?

March 15, 2009, 11:10 PM
unless the mag says usa (brand name not just made in usa) trash it. u can look online for sum usa made magazines (dont buy unless the pic shows usa on the side) gunbroker.com usually has a few up for auction. or u could get tapco 20's. trust me ive tested countless sks mags and none work reliable except tapco and usa.

March 16, 2009, 09:01 AM
that would be good advice, except this is an AK...

March 16, 2009, 11:45 AM
It sounds like it may be a heat issue. If it will fire the first three rounds when cold but then start sticking when it heats up a little, take a look at:

1....Varnish build up in the chamber. A lot of 7.62x39 ammo is painted with varnish. When it get's really hot, that varnish can melt onto the chamber and stick there. Then later, when it gets warm, it gets sticky like honey. Use a hone to polish the chamber.
2....Mis-aligned piston and/or tube. There may be enough clearance when it's cold but as it heats up, clearances change.
3....Built up crud inside the mechanism.

Give it a good disassembled cleaning, check #1 and #2 and post the results. Keep yer powder dry, Mac.

Tuff-Gun Finishes. The Name Says It All.
Mac's Shootin' Irons

March 16, 2009, 01:57 PM
After the range session today, I am definitely leaning towards #2 option, posted my Mac's below...

I believe there is actually a small spring or clip missing between the gas tube and receiver... that would definitely account for the excessive wobble on the gas tube... and probably isn't letting the piston do it's job either...

Thanks guys, anyone know where I might be able to find that part?