Vladimir
Detail Decepticon!
the blockage is located at the tip (like HP and micron tip)...I'll try with a toothpic now that you mentioned.
If it's really so, then it's not a problem at all.
The only thing is not to use any steel inside the nozzle, if you're not 100% sure that you wouldn't damage it. For me toothpick was enough to get rid of any paint material inside nozzles and other airbrush parts, no matter how old the dried paint was.