It only happens with this lower with an A2 stock.  Tried the upper on four different lowers without a problem.  So the upper is not the issue.  The bolt carrier does not seem to travel far enough aft to allow the bolt catch to engage.  It's only about a 1/4 inch further it needs to travel so the bolt face can clear the bolt catch.

It seems as thought the buffer is "bottoming out" in the buffer tube.  I tried three different buffers and all had the same result.  So the buffer is not the issue either.

Is the buffer tube damaged?  Is the spring messed up?  

I'm at a loss.

Your upper buttstock screw is prolly too long thus keeping the buffer from fully moving to the rear.

What Tweak said.

How long should it be?

Pull the butt stock and check for the A-2 adapter.  It is a cup that goes on the end of the receiver extension (tube) that limits the amount the screw can protrude into the extension.  

If you need to cut the screw, the fast way to determine the correct cut length to cut is just to look down the tube with a flashlight with the screw tight and see how many threads are protruding into the tube.  Then cut that that amount and an extra few threads to make sure that when you tighten up the screw in the future, you will not have to re-cut the screw.

P.S Since you have stated that the bolt needs to come back 1/4" more (plus there should be a gap between the two of 1/8") I would say that you are missing the A-2 butt stock adapter (the adapter is about this length).

Somewhere near 1.13", 5/8" longer than the A1 screw.

You may see a small cirular dent on the rear of your buffer where it is contacting the upper buttstock screw.

Some companies use commonly available screws that are slightly longer and some very long screws wind up in fixed stocks bc of all the stock extension kits sold out there.

Your buttstock screw should be parkerized, have a drain hole through the CL of the part, and show evidence of threadlocker.

Use thread locker (or the proper part) and a well fitting screwdriver when re installing the screw.

Gents,

Found a shorter buttstock screw amd it seems to have solved the problem.

One thing I did notoce though was that the head of the original screw seems awfully small and sank further into the trapdoor assembly than normal.

Thanks guys!