shamus, the kalashnikov will eat any .223 or 5.56 ammo...from wolf to barnaul to umc to remchester to mil-surp, it eats it all with high reliability.

the .223 ak's are the most accurate of all the ak chamberings. try as high-cap saiga rework or one of the vepr II's from robarms.

.223 bbl's. are made in russia, bulgaria (used on the sar-3 from romania), china, poland, east germany (the weiger).

"So why exactly were Russia and Bulgaria making .223 barrels for AK's?"

export sales. neither country has adopted 5.56 officially, yet. bulgaria may be doing so, soon, though...nato and all that.

"Just for resale here?"

and elsewhere. 5.56 is a nato std., so it opens up more market for them. a nato m-16 costs about what? $500 or so? an ak sells for under $200.

"Or did some eastern block countries go to Nato 5.56 after the Soviet collapse?"

yes. east germany and poland were early converts to 5.56. with romani and others joining nato last week, it is only a matter of time and finances before they convert.