I got it soaking in Kroil right now. Did some searches after I posted and the problem is more common than I thought. My Norinco SKS has the same problem but it shoots POA at 50 yards so no problem then.
They are tight -they have to be or they'd drift during fire.
Alot of the tools sold to move the sight drum just bust when you try to use them.
I use the Harley-Davidson method:
Lay the front of the gun, the sight base (on the barrel, of course) on a nice block of hardwood on the ground, held solidly...
Then, WACK THE HELL OUT OF IT in the appropriate direction with a good sized BRASS hammer. It will move (a little lube is a decent idea during the process).
Steel wool, lightly oiled, will remove the brass marks off the sight just fine.
The H-D method has never failed me on dozens of such drifting jobs.
Remember, the chinese AK & SKS has a CENTER MARK on the top of the drum seen from the front of the sight -you can guage movement by watching this ( the chinese usually zero'd the windage on these pretty darn well as made).
Have fun!
Lollygagger :wink: (IF you try to be a wiener with hits, the H-D method does not work.)