So I was in the mood to start looking at ARs. Been wanting to build or have a Pistol Caliber Carbine for awhile. Looking around I decided I could build one and it would be better than one I could buy of the shelf. SO I built myself an AR in 9mm. Got all the parts, build went OK. So far. I put everything together, go to pull the charging handle and cycle the bolt. The bolt won't release forward, it gets stuck on the buffer catch. Ended up breaking the NFA 2 piece bolt, sent that back to NFA and just got the replacement. Put the replacement in, and pull the charging handle, and again, the bolt gets caught on the buffer catch. I have to take the entire upper receiver off and use a curved tool to push the buffer catch down to get the bolt out and able*to separate the upper from the lower. What am I doing wrong? I have the buffer tube screwed in to the correct spot. I have the trigger assembled correctly, it functions perfectly when testing with the upper off. Lower and Bolt are New Frontier Armory. Buffer is a standard .223 buffer, but with a spacer for 9mm. The buffer catch Spring is bent now, so I'll have to get a new one of those.

Perhaps https://www.ar15.com/forums/ar-15/Buffer_problem__Help_please__/66-668277/

That was it.  Buffer tube wasn't screwed in far enough.  Thank you for the link.  Definitely won't be making this mistake again.