I just put another upper together and ran into a small issue thats driving me a bit nuts. I have the barrel nut tightened up pretty good but am not quite in perfect alignment with the gastube. I gave up for last night but think I may be able to budge it ever so slightly to get it right and thats a big "think". Its pretty snug thus far. If I were to back it off and then retighten it a bit less I feel as though it will not be tight enough. I lubed the threads and mating surfaces with some moly grease. I just don't want to got too far as I don't trust aluminum threads. I have never had this problem before. Any suggestions?

Tighten it down, back it off.  Do this 3 times and you should see a difference.

I backed it off several times and restarted the threads hoping its final resting position would change. I'll have to keep doing until its right. I just never had any problems before

read the tacked threads.



tighten, back off a bit, tighten, back off a bit, tighten....


it works it  closer to tighter indexing the slots further.

I'll try that

I thought that is what I said.....

You both did. Unfortunately, I've done it several times so I figure I'll just give it a shot again and hope it works. Otherwise, I need it to really turn another 1/32 to 1/16 of an inch and I am there. The gas tube goes in but would have to be held straight. That, to me, is half assed and plus I am pretty sure the carrier will get hung up on it.

Quoted: I backed it off several times and restarted the threads hoping its final resting position would change. I'll have to keep doing until its right. I just never had any problems before

from what i read this sounds like you are taking the bbl. nut completely off and starting over each time.

Quoted: I thought that is what I said.....

from what i read in his reply to your's it sounded like he though you said to remove the barrel nut and re-install 3x's

was just trying to make it clear.