OK. I’ve got a RRA upper with a barrel I can’t stand. I’ve decided to replace it with something better. Part of my purpose is to get some experience with AR maintenance; I’ve never changed a barrel before. I’ve gradually acquired all the tools necessary, but I need some tricks.
I got the gas tube retaining pin out easily and now comes the tube … which will not budge. I’ve tried pulling, I’ve tried clamping with several different sets of pliers and hammering the pliers toward the receiver, I’ve tried spraying the exterior of the tube at the points where it contacts the FSB and the receiver, and all I have is a scratched up tube that has not shifted one iota.
It appears that the tube is tight in the FSB. Should I remove or loosen the FSB (I wasn’t planning to)? Any suggestions or references I should look at?
Soak it overnight in Kroil.
If it’s still stuck, secure the gas tube in a vise (preferably with the jaws covered to protect the tube). Yank the upper away from the gas tube.
Thanks for the suggestions. I would rather keep the FSB on, but I may be forced to remove it if no other way presents itself.
I would gladly use a new gas tube when the new barrel arrives, but, thus far, it will not budge. I’ve been looking for Kroil for some time, but have yet to find it in any hardware or gun store I have found. Liquid Wrench?
The vise-on-the-tube idea has that “it’s gotta work” feeling (what with all the leverage involved), but it also seems like a grand way to mess up a receiver when it mashes into the vise due to my inability to stop its momentum in time.
I know you said you already tried pliers, but I’ve had good luck with modified needle nose Vice Grips.
Take a pair of needle nose Vice Grips, and about a 1/10th of an inch up on each side of the jaws, using a rat tail file, file a groove.
Adjust and tighten the Vice Grips around the gas tube, placing the tube inside the groove you filed. The smoothness of the groove will prevent damage to the gas tube. Now tap the Vice Grips with a plastic mallet, pulling the gas tube free from the FSB.
If the Vice Grips alone don’t cut it, soak the FSB gas tube port with penetrating oil, then try again.
i must be missing something… why, specifically, do you need to remove the gas tube? the old FSB cannot be used on the new barrel… you can just cut the gas tube off and pull it out to loosen the barrel… or pull the FSB and take it off at once
Please recall that I haven’t done this before. I have been following the various instructions I have been able to find and trying to follow them as well as I can, hoping that I don’t mess up.
I suppose that I can just cut the tube to free the barrel nut. Never thought of it. If I can not pull the tube out, I may just try that.
Of course, since I am tinkering here, I may try to pull the FSB. Thanks.
i wasn’t trying to be insulting, i just couldn’t figure out why you need to pull the gas tube, and everyone kept piling suggestions on as though you did, in fact, have some need to pull it.
i’d just pull the FSB, if i was jou. that way you can sell the barrel complete (unless you’ve already mangled the tube).
I’m just trying to let you all know that I barely know what I am doing (if that) and that all my knowledge is derived from someone else telling me what to do (i.e., I have no practical, hands-on experience).
One reason for doing this is to learn. For slightly more than the price I am paying for the barrel (Sabre) I could have just purchased a BCM upper and plopped it on.
Vice grips should do the trick. You can’t get a good grip with pliers. Clamp it down and tap with a hammer like Quip said. Also try turning it side to side a little to help brake lose the carbon build up.
He may want to sell the barrel and I think the ad will sound better if it doesn’t say “broken gas tube included”.
Take a hacksaw and cut the tube in half. Then grab it with some vise grips and it will come out. If I was rebarreling a rifle/carbine then I would replace the tube at the same time.
Thank, guys. I wound up cutting the gas tube and pulling a portion out through the receiver, giving me enough room to apply the armorer’s tool to the barrel nut.
I managed to strip the barrel nut on the first pass, and that is all on me. But, now the barrel is removed and I am ready for the next task (when the barrel arrives).
I now have plenty of time to figure out how to extract the tube from the FSB.
Yep Todd. That’s what I use to, it doesn’t leave any funky marks.
If a gas tube is really stuck do to carbon I’ll sometimes use Kroil and or freeze it for a while.
‘I got the gas tube retaining pin out easily and now comes the tube … which will not budge.’
It’s a legit question, but I did take care of it.
Sorry, I just had to supply the quote. I really am trying to do all the right things in all the right orders and following instructions very carefully. I have to. I have all the manual skills you would expect in an estate planning lawyer. :rolleyes:
