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Posted: 2/9/2017 12:24:35 PM EDT
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In the middle of trying to rebuild a crap upper. If I knew what I knew about ARs now, I would not have bought this gun. I have an authentic Colt A2 upper with an unmarked 20" HBAR. It was a parts gun with a three prong, A1 hand guards/grip, & A2 buttstock. So I put the correct furniture on, & all is good except the flash hider. Issues start here. It was installed without a crush washer; even with my tool for it, totally stuck. Well okay, I hate the HBAR anyway, may just swap the barrel.
Go to remove the gas tube and it won't come out of the FSB. Can fix that later, so I decide to just tap out the FSB pins & tap it forward so I can get at the barrel nut. Went really easy, as one taper pin was WAY filed down & the other not fully installed, just had one end mushroomed to retain it. Remove it and pin channels are awful - one is sloppy but otherwise seems okay, the other was drilled in the wrong spot & the correct one drilled near it. Barrel nut comes off and I notice the grease used is now some kind of blackish paste that reminds me of used up Teflon tape. Go to pull the barrel off, stuck Even with the upper in an upper vise block, & smacking it with a big hammer & 1" dowel, nothing. Heat gun didn't help. So my question is where should I go with this thing? I'd like to salvage the Colt A2 upper even if it is painted Krylon Black & just put a new barrel on it. I've thought about taking it to a gunsmith to try and extract the barrel and/or flash hider, but I'm curious what people think the condition of the upper will be at this point: concern is got stuck because of corrosion. My other option is to just sell it as is and salvage what little value I can, and just get a new upper. Of course the cheapest option is to probably put the upper back together as it shot okay before but I'm not fond of that idea. Other suggestions for getting the barrel out and flash hider off I'm open, won't fit in my freezer though |
I would try a torch on the flash hider. Not cherry red of course but about 350 deg. or so. You could also try that on the upper. Some HP shooters epoxied their barrels to their uppers. You might consider abrasive blasting the upper if you get the barrel loose and the cerocoating it. Colt parts do have a certain appeal.
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| Try some heat. The aluminum will expand faster than the steel loosening it up. Try heat on the flash hider as well, could be loctite. If that doesn't work, try soaking it in water overnight, could be rocksett. If none of that works, after you've removed the barrel from the upper, throw the barrel in some vise blocks and use a cheater bar on your wrench to get the flash hider off. |
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Thanks for the replies. Cheater bar on my wrench never occurred to me. I'll try that and some additional heat on the flash hider, again with mild heat on the receiver, tomorrow, see where I wind up.
The barrel taper pin slots are only ugly and sloppy, just indicative of how the gun was put together, and not a functional issue. I never had serious issues with wandering zero on it that would suggest they are loose. I'll just get some new ones when/if I go to put it back together. |
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Nope, not pinned. I can actually see gouge marks in the prongs from the tool and presumably from trying and failing to get it off before I wound up with it. So yeah, they put some muscle into it. Sorry for not mentioning that before, had to omit it from the initial post as I was way over the character limit. As for where I am at with it, no updates yet, sorry. Had other stuff come up and by the time they got dealt with I was in no mood to deal with this.
Want to give the flash hider removal one more try but I am pretty sure I am going to wind up writing this barrel off and try to just save the upper, as close inspection of the taper pins revealed the one that was all the way installed (versus the one that was not pressed in most of the way and then had the head mushroomed out to retain it  ) is actually slightly crooked... well when I lined up the FSB with the pin channels in the barrel you can see that they don't perfectly line up - when the FSB is lined up with one hole the other isn't. Probably because they look like they were cut on a cheap drill press with a Horrible Freight bit set. It's actually a miracle to me the gun zeroed and shot as good as it did. By Monday I will have gotten time to try again though, so I'll keep this updated.
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Quoted:
You could go a bit further and put the entire upper in the freezer and then heat the receiver to try to remove the barrel. |
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My suspicion would be that both the barrel extension and flash suppressor were installed with loctite.
Heat gun to loosen the loctite then they will probably come loose. Heat on the upper receiver will also loosen the fit due to the different thermal expansion of aluminum vs steel. |
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So I FINALLY got the flash hider off. What a pain in the rear. Tried a bigger, heavy duty heat gun, no help. Ultimately used one of those small butane torches like they sell at Horrible Freight to heat it to about 300 (used an IR thermometer to keep an eye on things), then put my flash hider tool on, my 1/2" breaker bar, a cheater bar, then grabbed a hammer. Finally got it off. The culprit was looked to be blue locked tight mixed with some corrosion and plain old torque.
Threads looked okay... cleaned it off with a wire brush and ran the replacement on hand tight (with a crush washer this time) and it seemed smooth, so I put a dab of oil on the threads, ran it to the proper torque, then took it back off. All good. Put it back on one more time, threw the gun back together and went shooting with it. Amazingly despite all my hammering on the upper it still shot okay, zero hadn't drifted much. So ultimately a mixed back. My very original goal before I posted, of getting the proper flash hider on, was achieved. But I'm a bit bummed I could not get the barrel off, as I was really hoping to swap it out. Maybe I'll revisit it later. Thanks for the help though. |
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