I am wanting to build something AK 105ish.   Not really,  just mainly interested in putting a Front sight/Gas block on a 223 Saiga,   My question is will the Bulgy one from KVAR work?  Also  Krebs makes one that clamps on,  will it work?  
Krebs Description..

Made from 4140 pre-hardend steel.  These Front Sight/Gas Blocks are taller than standard AK front sights, and are threaded for an AR front sight post (included).  Just the thing for the rifle "experimenter".  These gas blocks are BARREL DIAMETER SPECIFIC, and for AK rifles with a 45 degree angle gas port.  Please specify when ordering whether your rifle has a barrel diameter of .784  or .630.

I am building something like this,  Except not using the HK style sights,  I would like either AK series sights or the Krebs sight.  

Well first thing is you might want to measure the machined area of the barrel that the gas block sits on.

Then maybe just ask what the diameter of the Bulgy FSB/gas block combo is in the Bulgy forum.  I have nothing Bulgy.

I do know that the Romainian fsb/gas block combo is too small a diameter to use on my 223, unless the barrell would end right there.  It was around .570" iirc.


Have you considered cutting up the stock FSB and having it TIG welded to the gas block?