Ok, I know this is the wrong forum but it's after midnight and I need help pronto. The other day I got a RRA 9mm upper for one of my buds. For shits and giggles I thought I'd put it on my Colt lower to see what mine will look like when I eventually get it.

Looked good, everything was cool UNTIL I charged it. Now the bolt carrier is stuck in a halfway position. No matter haw many times I recharge the bolt it goes all the way back and only HALFWAY forward.

This means I CANNOT remove the upper. The bolt is holding it in place.

It is a RRA 16" 9mm upper on a preban Colt AR15 HBAR lower w/ A2 buttstock. I cannot get the bolt forward enough out of the buffer tube to remove the upper. It backs up and goes to the same point easy enough but something appears to be grabbing it halfway.

Does anyone know what is the problem? Or better yet got a simple easy solution to removing the upper without hosing either my Colt preban lower or the brand new upper that belongs to one of my favorite people?

TBS' solution will work. It's the .223 hammer that's blocking it, BTW, had the same thing happen to me when I built mine for m dad, and racked the acttion with the .223 hammer in it.

All locked up. Removing the buffer tube works, if it's still stuck, drive out the hammer pin to give yourself some more wiggle room.

Juggy

Hammer pin goes out left to right or right to left?

I usually drive it out from right to left, but I think it can go either way.

Hammer pin can be driven out either way-direction not an issue with AR15's.

and TBS, the top of the .223 hammer will usually catch a Colt-variant 9mm bolt.

Juggy

Thanks Juggy, I got it. You were right. Freaking hammer.