I recently purchased a Yugo SKS and I can't figure out how to lift the grenade launcher site?  I see that it has a little circle knob that twists and should move up to allow the site to move over it, but I can't seem to get it to move up.  It only screws down and up.  Any advice will be great.  Thanks guys!  

P.S.  Does anybody know of any good places to buy stripper clips?

The circle knob is the gas system shutoff.  just push it in and move it to the virtical position, don't twist it.  With the knob in the virtical position the gun will not cycle, you will have to cycle it manually for launching grenades.

As for the stripper clips...I have no idea, I bought some of the EE

www.ebay.com  type SKS seems to always have ton of accessoirs.

So's ya know, there's a third switch position, which is up and back.  It'll only work if you've pulled the gas tube, but it'll allow you to remove the selector button and spring and pull the gas selector out for a cleaning.  This is a good thing.

Oh yea, and once you get the grenade ladder up, it's gonna want to stay there.  This is normal.  Give it a whack like a karate chop to pop it loose.  If you hold on and push, it's going to pop loose and you're going to bust your knuckles, which sucks.