Hi,
I am relatively new to this forum but from what I have seen there are some very knowledgeable folks that post here.  I am hoping someone can give me some help on a problem I'm having with a new upper I just put together tonight.  This is about my 8th AR build and is the very first time I have ever encountered this problem.
When I put the bolt assembly into the charging handle and upper and slide it into the chamber to check the lock-up, the bolt lugs are very snug going in and mating up with the chamber lugs.  Then when I push it in as far as it will go by mild hand pressure, the bolt doesn't rotate and lock.  If I tap it with a small rubber mallet it will lock, but then I have to pry the bolt & carrier back out.  I tried three different bolt assemblies & charging handles and all with the same result.  Think I may have a bad barrel or maybe a "snag" on one of the chamber lugs?  I can't really see a problem, even when comparing it with another of my AR's.
Any suggestions or advice would be greatly appreciated.
Thanks
Thomas

I'm missing what barrel you are using.....

Its a heavy 11.5" from JSE Surplus.   Not sure who makes their barrels though...
I'll check it out.

its Wilson Arms Chrome-moly Barrel. 11.5" Heavy Barrel with 1x9 twist.

Have you checked the headspace? Don't shoot until you do I suspect the HS may be too tight.

No, I haven't check the headspace...and I definitely wasn't going to shoot  it, unless it was behind a wall with a 50 yard string attached to it! LOL
but the barrel extension was already installed, and fit was perfect on the receiver.  The barrel nut /gas tube alignment was right on at about 30 pounds torque.

Just put some valve lapping compound on it, then just work it over & over again in the evening while watching porn.

LOL!
OK, I tried that!  The movie got so good I could chamber a 50 BMG when it was over!

The fit of the barrel extension has nothing to do with headspace. The length of the chamber from the bolt face when in battery is headspace. Check it.

ok, we have an armorer out at the range who can check it out for me.
Im taking it to him tomorrow.
Thanks again.
Thomas

I'm no expert but my first inclination would be to blame the gas key/ gas tube combination.  I've seen a few soldiers bend the gas tube in overzealous cleaning attempts.  

You said you tried three bolt assemblies.  Does that mean only one bolt carrier or 3 different bolt carriers too?

Look at the gas key on the BCG, Is it straight?  Vertically and horizontally I might add!  If so look for the same thing on the gas tube.  I'd try pulling the gas tube out and then reinserting the BCG.  If it is still sticky then you know it is indeed the bolt/ locking lugs.

It's easier to check the gas key fitting before lapping any bolt!

My .02
Tom

Check the gas tube where mates with the gas key/bolt carrier. I had this same problem in Iraq and it turned out to be a bent gas tube.