I purchased a Vltor upper receiver from Noveske, and right off I realized that the Kreiger barrel I ordered won't fit the receiver.  So, I thought maybe it was the barrel extension.  Then I tried to insert the Young Manufacturing chrome match bolt/carrier assembly and it won't fit either.  Finally, I tried to install the charging handle for a trial fit and it doesn't fit either.  Do these upper receivers ship unfinished or is this just an isolated incident?  It literally appears that this upper didn't get finished.  Can anyone provide some insight?

Did you call Noveske or VLTOR?

Actually, I was trying to assemble it last night, which was after both their normal operating hours.  Being the first time I've actually built an AR, I assumed it was something I was doing incorrectly and was looking for suggestions on what I was doing wrong.  I've read about the quality of the Vltor and Y/M products and just figured the problem was in my methods and was hoping someone had experienced a similar issue and could give a helpful explanation last night.  I called Noveske today and spoke with a very helpful guy named Joel.  He was very polite and asked that I ship the receiver back.  Hopefully, I should know something Friday.  I'll post a follow up for anyone that may be interested.

im having the same problem with my vltor upper my barrel wont go in

Vltor uppers are built to minimum specs. Very good product. It sounds like you both are experiencing a tolerance stacking problem - minumum spec receiver maximum spec barrel extension and bolt carrier group. Try a standrd bolt. You may try placing the barrel and/or the receiver in the freezer overnight. Then see if they will slip together. As far as the bolt goes you may have to try a standard bolt carrier instead of the one you already purchased.

Vltor receivers have been shipping with the extention area tight.  If you heat it with a propane torch you should be able to fit the extention in with little effort.  At least thats what I did.  As far as the carrier, not sure.

It does seem there is an issue at hand.  This is the third thread I've seen in the last few weeks dealing with this.  

http://www.ar15.com/forums/topic.html?b=3&f=4&t=419693

http://www.ar15.com/forums/topic.html?b=3&f=4&t=421304

-1000 on propane torch.  The receiver has a specific heat treat to it and it is very easy to heat aluminum up to the point of changing the heat treat.  Freeze the upper and extension as suggested above.  Use dry ice if need be.

Heating with a torch is fine.

But I won't heat aluminum hotter than I can handle to touch.

Stick the barrel in the freezer and warm with the torch.

 Agreed ! I've built 2 uppers on Vltor receivers and they are indeed a tight fit . Freeze the barrel and extension and nothing more than a hair drier to warm the receiver . It will then tap right in . Take care with the alignment pin and notch .

Wouldn't you want to freeze the barrel/extension and warm the reciever?  

I had a very tight fit with my VIS upper & Noveske barrel.  I was just able to press it in by hand which is optimum in my opinion.  I had to have the fit between barrel extension and reciever shimmed on my JP/DPMS .308 because the poor fit was causing poor accuracy.