I'm going to try and build an old style AK and I'm looking at CNC warriors milled receiver. I'm looking at getting a Romanian 7.62x39 Parts Kit from AK builder. Would I run into a problem fitting that barrel into the receiver?


edit I don't know why i called it a billet

Yes, the diameters for Romanian AKM barrel and AK-47 barrel (which is what CNC warrior receiver is made for) are different.

So what barrel am I looking for

This one:

http://www.k-var.com/shop/AK-332CL.html

thanks

But that barrel will not work with the rest of your Romanian AKM kit.  If you want to build a milled AK, you'll a milled kilt, like the Bulgarian one here.  That, plus the CNC milled receiver, plus K-var barrel, should be good.  Of course at that point you're in for about $600 before any build fees.  If you just want a milled AK, I'd buy one of the CAI Polish ones or the new K-Var SLR-101s.

I plan to build it myself.

Actually you can make it work with just the Romanian AKM kit.  There seems to be a lot of confusion here as to the barrel components size versus the barrel trunnion size.

The diameter of the hole in the  trunnion for the barrel is the same size for the milled Ak-47 receiver and for a stamped AKM style.   They are both 23MM (.908).  This means that either an AKM barrel or a milled style barrel will fit correctly in the milled receiver.   The big difference is in the outer diameters of the barrel where the components are.  Because the milled AK and stamped Ak barrel have different diameters where the RSB, GB and FSB are, those parts are not interchangeable between the two styles.   If you go with a milled barrel you have to go with milled sized compnants, if you go with a stamped barrel, you have to go with AKM sized components.  

So long story short, you can use the Rommy G kit for the build as long as you you use an AKM barrel. Like this one from Apex Romanian barrel   It will fit in the milled receiver since the hole in teh receiver for the barrel is the same size. Only other minor issue you will have going that route is the channel for the RSB in the receiver is wider for milled parts.  So if you use the Rommy G RSB you will have a slight gap on either side of the ears of the receiver in the channel.  Will not affect function at all.

2  things to consider here in making a decision

1–– Are you looking for an accurate representation for a  build?  If so you will have to get a milled parts kit and use a milled profile barrel.  That equals more money, but more accurate in terms of correct parts with a correct profile barrel.

2- Are you looking for a shooter that looks the part?  Then the Rommy G kit and AKM style barrel would be just fine and cheaper.  

All that having been said, I would like to suggest a route for you to go

1–– Use the CNC warrior receiver

2- Buy one of the Milled Bulgarian parts kit like the one linked above

3- Buy a Yugo barrel for cheap.  Centerfire Yugo Barrels  Many are in nice shape but ultimately they are used and are a crap shoot.  So buy three, keep the best and sell the other two for what you spent on them.   The Yugo barrels are the same diameter as the milled components.  There is some extra work involved as the handguard retainer will not be at the right location (will have to be re cut further back, and the RSB will have to seated further up than where the Yugos seated them.  But it is definitely doable.  

this method will save you  alot of money versus buying the barrel from KVAR, but will require a little bit more work on your part for the build.

I built this Spiker clone using the Yugo barrel and Bulgarian milled components just like I am suggesting. (well all except the Chinese spiker FSB  )  


Detail showing the old HG retainer slot, and you can see how the new one is cut further back.  The old retainer hole can be welded up for aesthetics if you so desire


And here is a shot showing the RSB and how it sits further ahead (I built mine into a stamped trunnion, but it would be the same on the milled receiver)

Ok, now let me get this straight. I can use my Bulgarian Milled AK47 Underfolder parts kit, use a Yugo Barrel and a Yugo Front trunnion, perhaps a NodakSpud UF stamped receiver and build a perfectly functional if not accurate looking rifle ? I am not looking for ascetics just function. If that is the case then I can also save a bunch of money on the milled receiver.