I ran into a weird problem with my LBC bolt carrier that I have never seen before.  I installed it into my rifle (Wilson Combat matched upper & lower)  w/ a PRI gas buster CH, I go to charge the weapon and the bolt carrier jams up about 3/4 back and sticks there.  I have to take the take down pin out to get it to un stuck.

    This is all new stuff and I see some weird rub marks on the gas key and some marks on the inside of the buffer tube.  I suspect that this carrier is out of spec, maybe even the key is crooked?  

   I put a CMT BC in the same rifle and it works fine, no drag.  I put a Colt BC in the same rifle and again no problems.  

   Here's the catch, I put the LBC carrier in my RRA M4 and it works OK (I can hear some slight rubbing in the buffer tube when it is pulled back all the way, but it does not bind up or get stuck.

  Now what ?  Send this BC back to Brownell's and try again?

  At first I suspected the buffer tube, but other BC's run fine it this rifle.

  Anyone ever run into this problem?

first i would try to lube the piss outta the upper and BCG and charging handle....then i would try to work it back and forth a few times to create some wear points and see if it loosens any....if that doesn't work then i would begin calling the company.  or you can just call the company and hopefully they'll make it right for ya

I lubed up everything with CLP and worked it, I can now get the bolt back to the bolt catch, but it stays stuck there now, until I pull out the rear take down pin, then it slides home by itself.  

The upper and lower fit together nice and tight, I would think there is a alignment issue with them but other bolt carriers run fine in it.

I'm thinking a call to Brownell's might be in order.

I'm wondering if the buffer tube may somehow be out of spec?  Maybe the ID

Does anyone know what the ID of the tube is supposed to be?

Check if the hammer is draging on the carrier, Some times if something (Upper, Lower, B/C or hammer)  is slightly out of spec this causes the Bolt carrier to hang up. This used to happen alot in the early days of aftermarket ARs when quality control was not what it is today.

That's what I thought at first, but it is now sliding past the hammer and just past the bolt catch.  The bolt catch won't catch though because once the bolt gets that far back it just gets stuck there (inside the tube).

This thing is pissing me off.

The LBC carrier works fine in my RRA M4, maybe I'll just leave it in there and call it a day?