Removing AA Floating Handguard and Gas Block from Overwatch Upper - Help Please!

[fallschirmjäger]

As stated in the title, I'm trying to remove my barrel to send it in for threading, as my Form 4 should be approved soon (30P-1). Last night I went past the point of frustration trying to get the handguard off, as well as trying to break the gas block loose.

I had the upper receiver fixed in my vise with one of those internal blocks, and using a strap wrench I couldn't get the handguard tube to budge. I put heat on it to no avail, and finally gave up. I went online and saw someone mentioned that you might need to take the gas tube out first, which sounded fine to me because I figured this thing was on so tight the barrel nut might budge before the handguard did, so I popped the pins out and, like the handguard, can't get the gas block to move. At this point I'm almost ready just to pay the $50 shop fee for disassembly, but would rather spend that on a new railed handguard or anything else.

Thanks in advance!

[ricsmall]

Probably need to heat the gas block to 400 degrees to remove the 243 Lottie applied at factory. Which hand guard is it?

[fallschirmjäger]

It's the fiberglass round tube. This is an older upper from AA, so it's just the old black tube.

[jurassic]

I would try to contact AA. I'm sure everything is glued on, including the barrel nut, barrel, gas tube and gas block.

[fallschirmjäger]

Glued? Por que? I mean, is that typical on AR-15's, or just an AA practice?

[ricsmall]

its a widespread practice, especially from AA, who does this to try and prevent small differences in tolerances from robbing accuracy, and creating malfunctions. People in highpower competitions use these practices as well to enhance accuracy, and more and more home builders of ar's are doing for same purpose.

[rasp65]

This is from a post on this forum by Bill Alexander. "It is not difficult to remove a barrel that has been bedded with loctite just as long as the correct grade is employed. We typically use Kroil and a little heat (hand hot) It is not good to use excessive heat as the aluminum will heat treat at temperatures of that can be attained by hot air blowers. Time is always your friend. Apply, heat and then go and do something else for a day and let the Kroil do the work."

[Bike Effects]

This is from a post on this forum by Bill Alexander. "It is not difficult to remove a barrel that has been bedded with loctite just as long as the correct grade is employed. We typically use Kroil and a little heat (hand hot) It is not good to use excessive heat as the aluminum will heat treat at temperatures of that can be attained by hot air blowers. Time is always your friend. Apply, heat and then go and do something else for a day and let the Kroil do the work."

I for one would like to know what type or grade of Loctite Alexander recommends. My original receiver on my .223 AR was from White Oak Armament and the barrel was installed with red Loctite I installed the barrel on a LAR OPS-4 receiver and used blue Loctite. The chance of getting red Loctite on the barrel nut intimidated me.

[jurassic]

If I remember he said they use 620 or 609, it's green and made for seating bearings (round things into round holes,) or other similar applications.

[ricsmall]

everything ive seen said 242 or 243 loctite. I was wondering about the bearing seat loctite, sounds like it would take a lot of heat to remove.

[LRRPF52]

I just went through this process when I removed a DD RIS II handguard from an AA 20" GDMR for the Cerakote job I did.

Tap out the gas block pins if you can. I use the Brownell's installation/removal block that I modified to work with circular low-pro gas blocks, as well as the standard FSB. To release the Red Loc-tite, you do not need insane high heat, but just some time and patience with a hot air gun or hair dryer on high. Apply heat to the gas block for several minutes, then use a strap wrench to break the fit.

You need to clamp the barrel with insulators when applying torque to any part that is attached to it, not the upper receiver. If you can get the handguard off itself first, not the barrel nut, do that.

Punch out the gas tube roll pin and remove the gas tube. You can do that only if the handguard tube is removed. To get the gas block off after the pins are removed and heat has been absorbed enough to break the Loc-tite, you will need to tap the block off with either a large Delrin piece or brass, insulating the barrel from any stray blows and resulting surface damage.

Once you get the block off, take some Kroil or penetrating oil and apply it to the crevice between the barrel nut and the upper receiver threads.

Let it sit overnight, or for no less than 6 hours

See above.

No really, you need to let it sit and allow the oil to do its job.

At this point, I applied heat to the barrel nut, because copious amounts of Blue Loc-tite had been used to bed the barrel extension to the upper receiver, and the gun shoots lights out, so I ain't arguing with anyone who does it.

Once the nut was heated enough for me, I was able to break the seal and turn it off of the upper.

When I re-assembled, I placed the gas block in the freezer, because it was an anus to get off. I cleaned the Red Loc-tite residue off of from inside using fine sandpaper lightly. After the block was in the freezer for about 2 hours while I had been installing the barrel and barrel nut, again with Blue Loc-tite, I was able to literally hand-slip the block over the gas block journal right into place. I literally prayed before that it would go on smoothly, because it had been such a pain to remove-the hardest gas block removal I have done since 2003. I was pleasantly surprised by how well it slipped into place, and I attribute that to the molecular shrink dimensionally, as the ID moves away from the center of the gas block, as well as the OD moving towards the center.

If you follow these steps, and know your way around several barrel changes on the AR15, you might get it right. I'm concerned that you applied torque to the handguard with the gas tube in-place, if I read correctly. It's probably a good thing that it is Loc-tited, because that could cause some damage if the handguard started to turn.

[OFBHWG]

AA puts some serious thread lock on their barrel nut! I had to finally end up cutting the nut in 2 pieces to get it off of mine!
Used a thin blade dremel cutoff wheel.

[Bike Effects]

AA puts some serious thread lock on their barrel nut! I had to finally end up cutting the nut in 2 pieces to get it off of mine!
Used a thin blade dremel cutoff wheel.

The barrel nut itself should be installed with an Anti-Sieze compound. Loctite can be used on the barrel extension.

[sureshot]

Use the heat and cutoff wheel if needed. Then get a better tube!!!