Hi, new here :)

I bought a PWS MK114 upper and just finished a lower build for it.  When I finally put everything together I found the charging handle stuck - I cannot pull the charging handle and it seems to be stuck at somewhere before going to the buffer tube.

Here is the list of parts that I used:
PWS MK114 upper
Spartan Billet Lower (from Joe Bob)
PWS Enhanced Buffer Tube
buffer and spring seems unrelated to this problem

Some troubleshooting I did: I removed buffer and spring; I removed the buffer retainer (thought it might get into the way because PWS bolt carrier has a smaller groove for the retainer); none of this helps, pulling the charging handle can't move the bolt carrier even without the buffer, spring and buffer retainer.

I tried fitting the bolt carrier into the buffer tube, and it fits, although seems a tighter fit than others. I then tried the same lower with a Colt 6920 upper and everything works; I also tried the MK114 upper with the Colt 6920 lower and it worked perfectly.

My guess is the PWS bolt carrier is slightly larger than normal and my lower receiver is a little bit mis-aligned? Anyone else seen this kind of issue, any thoughts? Thanks!

Here are some pics that I took:
looking at the bolt carrier with buffer tube removed

that's as far as I can get when pulling the CH

Does the BCG move?

I can't tell for sure, but the hole for the buffer tube appears to be offset to the right a bit.

Take the upper off the lower (you'll have to push the bolt carrier all the way forward first) and then try pulling the CH back and see if it's still jammed.

BCG doesn't move either, I am guess it's the bolt carrier that's being stuck
the upper works super fine, when installed on my colt 6920 lower

it's not jammed, the upper works fine with my colt 6920 lower

Is your buffer retaining pin sitting down far enough?

There seems to be a noticeable gap at the rear of the receivers' in front of the receiver extension threaded bore.  I wonder if the rear pin location is a bit higher and is causing the upper to sit higher than it should when attached to that particular lower?

I actually removed the buffer retaining pin, buffer, and spring, and still cannot pull CH

there was no gap as far as I can recall, in the pic might be because of the shade, let me double check and take more pics, thanks.

I had a similar issue with my billet lower and mk114mod1. If i lifted up on the CH it would clear the lower and oull back, so i ended up sanding the underside of the CH down and now its perfect.

So i guess just make sure it isnt hanging up on the underside of the Charging handle. Sure uou already did but JIC

Had same issue with mo110 and pws tube. First, read the instructions for installing the pws tube.  Screws must be tightened in specific order. And the lower bolt CANNOT be over tightened.

I tried another buffer tube (a normal, mil-spec one) and it still doesn't work, that makes me think it might be the spartan lower, I tried the upper on my other lowers, and they all work...

One other thing to try. Is the picture with your PWS buffer tube started in the lower how you have it set up? That buffer tube is made to be screwed in all of the way! I mean all of the way, there should not be any visible threads like a standards tube. BTW what is holding your detention spring in for your rear take down pin? You need to look at some PWS pics closely to see what I mean.  On your buffer tube there is a groove cut out on the bottom for the buffer retaining pin, you will need to press the pin in and rotate the tube several more times each. On mine when the buffer tube tightens up I put the stock on it and have to really reef on it to get it the last 1/8-1/4 turn depending on the rifle.  You should also have an end plate there between your lower and where the castle nut would be if that was a standard buffer tube. Actually I am not 100% sure there is an end plate! I will have to look tomorrow. I am thinking your BCG is just jamming because the buffer tube is not inn all of the way, should work smooth as silk when you have it all together.
Good luck!