Can a Bulgarian be built on this and are they any good?

http://www.brownells.com/rifle-parts/receiver-parts/receivers/rifle-receivers/ak74-5-45x39-receiver-blank-prod74993.aspx

TYVM Everyone

If by Bulgarian you mean a Bulgarian AK-74, then yes. Yes, they are very nice shells and are produced by a military factory. Now, they won't be "correct" for a Bulgarian build if you're concerned about that, they're also a fairly involved build process using one of those blanks. If you don't have access to a heat treating setup I would suggest buying one of the pre-hardened shells from Childers:

https://www.childersguns.com/AK-Receiver-Blanks-80-Percent-heat-treated/AK-74-blank-rails

with that receiver you will need to heat treat the receiver and if done incorrectly it can warp and also you will have to spot-weld the receiver rails which are not included and would have to buy separate. I went with the nodak spud receivers that were already heat treated and the rails spot welded just need to drill the holes to fit the trunnions. I also heard that childers makes good receivers too. but if you have a spot welder and know how to heat treat then you can go with that. or go with the ak-builder flat and then bend it to get where this receive is and save some $$$ and the receiver rails are included. ak-builder makes good stuff and I bought most of my stuff from them.

I'm not aware that NoDak Spud sells 80% receivers. Link?

Ok TY all for the advise, I think I'll spend a little extra and go with the Childer's.

http://www.nodakspud.com/AK%20Receivers.htm I bought a ak 74 and a polish underfolder from them great receivers. I went with the blemish ak 74 and it was in great condition and I could not tell the difference than by polish underfolder receiver and save some $$$ by buying it.

Okay, those are 100% receivers. That's why I was confused.

I went with a recreator blank recently. Was more than happy with it.