There's a notch cut on the end of the tube that goes into the receiever - is it supposed to go in any particular position like 6 o'clock, etc.

Thanks!

Yes, it goes in the 6 o'clock position - downward as looking at the recoil plate of the lower... Positioning it that way gives necessary clearance for the rattail of the bolt carrier... I like mine to be tight, so if your's "overtimes", what I've done sucessfully in the past is to carefully file off enough from the end(not much, mind you) so that it'll come around again - only tightening in the proper position this time around.... Then, I make sure I still have proper clearance for the rattail, and use a round file if necessary... Some may disagree with this, but I degrease the threads and apply some red locktite on them before installing the recoil tube - I've had a few come out instead of the nut when removing a stock - and it's a bit annoying... Besides, recoil tubes don't get replaced all that often, and a bit of heat on the tube will break it loose again despite the red locktite...



 - georgestrings

Quoted: Yes, it goes in the 6 o'clock position - downward as looking at the recoil plate of the lower... Positioning it that way gives necessary clearance for the rattail of the bolt carrier... I like mine to be tight, so if your's "overtimes", what I've done sucessfully in the past is to carefully file off enough from the end(not much, mind you) so that it'll come around again - only tightening in the proper position this time around.... Then, I make sure I still have proper clearance for the rattail, and use a round file if necessary... Some may disagree with this, but I degrease the threads and apply some red locktite on them before installing the recoil tube - I've had a few come out instead of the nut when removing a stock - and it's a bit annoying... Besides, recoil tubes don't get replaced all that often, and a bit of heat on the tube will break it loose again despite the red locktite...  - georgestrings

Good info here, I've done the exact same thing on my last ZA build.