Hmmm. It would be wierd to have the feed ramp be blocking anything, being that a barrel used to be headspaced in this rifle.... the other variable however is Vartan's barrels....I have a take off barrel, so I know it will headspace and work.... these new barrels I have inspected and quized Vartan about, but I have not used one for a build... I am sure they are faced properly and all that, so I doubt it is an issue.. but I wonder....
At this point, it sounds like it might be seized up in there... I would pop that puppy out and emery cloth the journal for a smooth fit... lube it up on it's return into the trunion.... every AK barrel I have ever done it was possible to go past the point of perfect headspace, this combo should not be an exception. THere are these guys that have to have a .002-.004 press fit to be happy, I think that is insane...of course you don't want to be able to push it all the way in by hand, but a slight interference fit along with that fat barrel pin is going to be just fine.
Bummer about the handgarud too, how are you going to build it up? put a spacer in the receiver? One more vote for the Vepr!
-C