Stuck gas tube

[OLIAR15]

Why are you removing the gas tube?

I am swapping uppers only, not barrels, so barrel has to be removed, which can’t be done without removing the gas tube first.

[OLIAR15]

Ok thanks all again. Victory is mine, it finally came out without damage with locking pliers and thick suede leather which offer grip and protection.

Hate it when the 30 minutes job turns into 3 hours with minor burns, scratches and cuts.

[MistWolf]

- Remove the barrel from the upper
- Apply penetrating oil to the gas tube and FSB and let it soak
- Remove the roll pin holding the gas tube to the FSB
- Turn the barrel assembly upside down and clamp gas tube in a sturdy, smooth jawed vise near the FSB.
- Using a dead blow hammer, firmly tap the chamber end of the barrel. Support the barrel in your off hand until the gas tube separates from the FSB

Using Vise Grips is doing it the hard way and will damage the gas tube.

[Pat_D]

As far as the stubborn gas tube goes, If you have a vise, flip the receiver over and clamp the gas tube in the vise. Now you can use a wooden or rubber mallet and tap on the back side of the upper receiver. It should break loose.

[FISH5742]

- Remove the barrel from the upper
- Apply penetrating oil to the gas tube and FSB and let it soak
- Remove the roll pin holding the gas tube to the FSB
- Turn the barrel assembly upside down and clamp gas tube in a sturdy, smooth jawed vise near the FSB.
- Using a dead blow hammer, firmly tap the chamber end of the barrel. Support the barrel in your off hand until the gas tube separates from the FSB

Using Vise Grips is doing it the hard way and will damage the gas tube.

Thank you! That seems to be much better advice than I gave. I will try this next time.


- FISH5742

[OLIAR15]

- Remove the barrel from the upper
- Apply penetrating oil to the gas tube and FSB and let it soak
- Remove the roll pin holding the gas tube to the FSB
- Turn the barrel assembly upside down and clamp gas tube in a sturdy, smooth jawed vise near the FSB.
- Using a dead blow hammer, firmly tap the chamber end of the barrel. Support the barrel in your off hand until the gas tube separates from the FSB

Using Vise Grips is doing it the hard way and will damage the gas tube.

Sorry but how do you remove the barrel with the gas tube in place ?

You can unscrew / rotate the barrel nut with the gas tube in place, you have to remove the gas tube first.

And that was exactly my issue, can’t remove the barrel before the gas tube.

[OLIAR15]

As far as the stubborn gas tube goes, If you have a vise, flip the receiver over and clamp the gas tube in the vise. Now you can use a wooden or rubber mallet and tap on the back side of the upper receiver. It should break loose.

That’s a very good idea, I’ll try that next time.

[MistWolf]

Sorry but how do you remove the barrel with the gas tube in place ?

You can unscrew / rotate the barrel nut with the gas tube in place, you have to remove the gas tube first.

And that was exactly my issue, can’t remove the barrel before the gas tube.

You know, sometimes the Old Wolf shows signs of senility!

- With the BCG, charging handle and hand guards removed, turn the upper upside down and clamp the gas tube in a sturdy smooth jawed vise near the FSB. Using a long brass rod and a hammer, tap the barrel at its chamber until the gas tube comes free

[Dennis]

- With the BCG, charging handle and hand guards removed, turn the upper upside down and clamp the gas tube in a sturdy smooth jawed vise near the FSB. Using a long brass rod and a hammer, tap the barrel at its chamber until the gas tube comes free

I like this!

I have a MOACKS from Ned that I have used on obstinate gas tubes but I really like your method. Vise bigger!

However the MOACKS aids stubborn reinstallation as well.

http://www.m-guns.com/tool_new.php?product=moacks

Love learning new methods!

Dennis.

[goaltendah1]

Have you tried to heat the gas block/tube to see if that will loosen it? My guess is that you have a little bit of carbon buildup. Heat may or may not work, but its something to try if you already haven't.

On the taper pin, I found that a heavier hammer with the proper support will usually knock the pin loose. Oddly enough I was helping a friend this morning with building an upper and the taper pins on the Colt FSB were in there pretty good. Used a large punch top get them moving with a heavy hammer with the barrel resting on a Wheeler AR-15 Bench Block (https://www.midwayusa.com/product/1016339811) resting on concrete floor. One pin gave in fairly easily the other was a super PITA. Got it out though. It helps having a second person to hold the barrel in place so it doesn't shift.

Good luck!