AR Barrel nut removal. Finding out the hard way.

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fin

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For those interested in installing a foregrip, you might want to prepare yourself. I thought I was just going to buy a barrel nut wrench and screw that puppy off. After some research and personal trial and error, I realize that many brands of new AR's have this thing torqued down REALLY tight. Long story short, what is needed on most new AR's is:

- good Barrel nut wrench with a handle that allows long leverage or attaching a long leverage arm. Don't cheap out on this or you will just get pissed off and possibly damage your rifle. ($35)
- an upper vice block ($35)
- a vice ($$$)
- Torque wrench ($40)

In other words, getting a gunsmith to do this might just save you some money if you are not planning to do it more than a few times. Here is the longer story:

I recently bought a Troy TRX, expecting "minor" gunsmithing. Getting the gas block off was a cinch, the barrel nut is something else. I am working on a brand new PSA rifle. I ordered a Barska AR wrench, which I realize is a mediocre tool, but for $15 I couldn't resist giving it a shot. Hindsight I might try the PRI wrench which has 5 prongs. Three prongs is just not enough contact for the torque required.

To begin with I tried using the three prong side of the barrel nut wrench, which fits well, but this thing is on there really tight. After breaking some teeth, I moved to the opposite side which engages all of the teeth on the nut. The only good thing I can say about the barska tool is that it did engage the mil-spec nut adequately. The problem is that this side constantly wants to get pushed off the nut by the Delta ring. This is why the five prong tool may work well, because the prongs slide in under the delta ring.

The problem with the barska combo wrench is that you can't really slip a steel pipe on it to increase your leverage because both ends are wrenches, or at least it would have to be a decent size pipe. Also, the half-inch cut-out is too large, so inserting another leverage wrench doesn't mate firmly at all.

Without a vice, I was sitting on the receiver which was wrapped in a towel on my work bench, pushing the wrench into the nut against the delta ring with one hand, and framming the other end of the wrench with a hammer. It wouldn't budge. Then I tried standing on the wrapped receiver, and powers-quatting the wrench. It still didn't budge. The next step will be making this a two man job, having a friend stand on the receiver, while I stand on the barrel, and we both jump up and down while pulling on the wrench. If that doesn't work, I will just grab the barrel with both hands, and swing it like a baseball bat into a tree or the side of my house to see if it will loosen up a bit.

In the end, I determined that I can either buy a vice, another wrench, and a vice block. Or I could be patient and send it to a gunsmith and probably save some money as well as some damage to my rifle.

I realize that this was not a professional approach, but I wanted to share some humor, vent some frustration, and maybe give someone interested in doing the same a heads up.

Oh by the way I have hear of using heat to help loosen things up. Does anyone know how to detail that procedure? I am not really sure how I could effectively heat up the barrel nut.
 
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Just heat the upper.

If there is lock-tight, it will smoke it out.

In theory:
If the nut is just super tight, it will expand the threads in the upper away from the nut threads.

Heating the nut would expand the nut threads in the upper and make it even tighter.

rc
 
Wow thanks for sharing that. this is why i'm not upgrading to a free-float for now, just a standard quadrail replacement.

for all that headache you went through, the gunsmith option might've been a better approach.
 
Loctite, and heat is your friend.

Heat the nut until you see the first whisp of smoke coming from the joint and then attempt removal.

Heat softens thermoset plastics like anaerobic threadlockers.
 
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With all due respect, when doing work on firearms, it is cheaper by far to invest in the proper tools of good quality to do the job correctly. This means a good vice, correct fixtures, wrenches and screwdrivers.
The investment paid now will save much agony, busted fingers, damaged firearms, and foul language in the future.
I know, it sounds like sniping at you, but years of experience and not a few damaged guns have taught me the lesson and reinforced the education.

Roger
 
Without a vice, I was sitting on the receiver which was wrapped in a towel on my work bench, pushing the wrench into the nut against the delta ring with one hand, and framming the other end of the wrench with a hammer. It wouldn't budge. Then I tried standing on the wrapped receiver, and powers-quatting the wrench. It still didn't budge. The next step will be making this a two man job, having a friend stand on the receiver, while I stand on the barrel, and we both jump up and down while pulling on the wrench. If that doesn't work, I will just grab the barrel with both hands, and swing it like a baseball bat into a tree or the side of my house to see if it will loosen up a bit.

I hope you have video of this. Please post it one Youtube, Please!:D

JT Armorers Tool, Upper Receiver Block and a Bench Vise makes removal pretty easy. Add a Torque Wrench and some Anti-Seize Grease and you’ve got everything needed to put it back together.
 
There isn't supposed to be LokTite on the threads. There is supposed to be a dab of high temp grease (2 diff metals, to prevent them from corroding together). I actually use a high temp anti-seize.

I'm surprised that your Troy rail didn't come with a wrench. My new Troy VTAC did...very beefy, it has replaced my other wrench now.
 
With all due respect, when doing work on firearms, it is cheaper by far to invest in the proper tools of good quality to do the job correctly. This means a good vice, correct fixtures, wrenches and screwdrivers.
The investment paid now will save much agony, busted fingers, damaged firearms, and foul language in the future.
I know, it sounds like sniping at you, but years of experience and not a few damaged guns have taught me the lesson and reinforced the education.

Yeah I know, No worries. I am experimenting and having fun with it. "One day" I will have the cash to do everything the right way. For now, I will have to humor myself with my mistakes here and there.

I hope you have video of this. Please post it one Youtube, Please!
Sorry, no video, but maybe next time!

I'm surprised that your Troy rail didn't come with a wrench.
As for the Troy wrench, the TRX has its own proprietary barrel nut that is a different size than mil-spec, so it does come with a wrench, but not one that fits the current nut. These actually used to come with a double sided wrench, and I was disappointing to see that mine did not.

I appreciate the generosity MtnCreek, but I am in VA. I will be taking it to a smith this weekend, so its no big deal.

I am still curious as how to apply the heat. Do you lay it on the stove or something?
 
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They don't need to be on that tight usually, the spec. is what, 30-80lbs? That is pretty variable and tells you "torque" isn't the issue, but "over-torquing" is. And loctite is the wrong stuff to use, I think it is moly lube. But I use TW25B, I found out that one of the better manufacturers use it too (KAC maybe?). I also hand torque it back on, the gas tube lines everything up --no torque wrench needed. Once you've done a few you don't need the torque wrench anymore, but it is kind of important until you know what to look for. Catch 22 there.

Yes, you do need the vice and block. A real wrench is nice too, one that grips all teeth if you are working with those. This stuff is required, even if you can get it off and back on without it (in one case I did, and in another I didn't) you risk damaging the receiver. They are just thin aluminum where you are doing all that torquing.

A strap wrench is nice to have too, especially if you deal with the KAC FF rails.

And worse thing that will happen if you don't get it tight enough is that you'll notice your barrel is a little loose --you'll get the hint when you get 20MOA groups. But it is an easy fix then, just redo it and move it one notch over if you can.

An old leather belt, cut in four peices and doubled up, make nice vice blocks for the barrel in a pinch, but don't go too tight. You can damage things with torque but not be able to see the damage.

Worst thing ever to torque off was an STG58 flash hider.
 
A vice and action block is your friend, as is a quality wrench. I use DPMS blocks and multi-wrench, and have zero issues or drama.

Just sayin'.

:)
 
I am still curious as how to apply the heat. Do you lay it on the stove or something?

I had similar issues with a buffer tube on a Beretta 391 shotgun. I used a 'camp' gas bottle w/ a small torch head. Apply heat, don’t cook it.
 
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I have removed several free float tubes and barrel nuts from factory rifles (when you have the tools its amazing how many "friends" you will have with AR's). Each and every one I took off had loctite from the factory on the threads and a little heat will liquify the loctite and make it easier to loosen the nut. Red loctite is a half step away from a spot weld on the threads. I have seen a ton of broken tools and busted finger due to loctite. Loctite will tell you heat the red stuff before you even try to take it off. The blue, purple and green you can muscle off, but the red solidifies after a few days and will not "break loose". Heat and proper tools is the only way to avoid broken parts and fingers.
 
I recently attempted to remove a 20" barrel from a brand new Del-Ton upper, the thing absolutely would not budge. I attempted heat along with a 24" breaker bar with no success. I wound up cutting the delta ring, spring, and barrel nut off due to the reason I was simply replacing them with a free float hand guard. Read later on that placing the upper in a freezer for a few hours could have helped with barrel removal.
 
A vise mounted to a bench will do wonders. I use a craftsman torque wrench and a combo wrench with the 3 pin setup. I have only had one or two barrel nuts where I broke teeth. They were really on there and heat would have broken them loose. Other than that I have never had an issue with that setup. I have done close to 1500 rifles with that tool. I used to work for an AR-15 manufacturer.
 

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Wheeler or Brownell's clamshell, Geisselles reaction rod, or the PMAG tool all work. I generally use the Brownells clamshell for barrel installation as it supports the receiver (those are pretty fragile) a bit better and it has a gas tube alignment function (those are pretty fragile). Both the PMAG and Geisselle lock into the barrel lugs in the barrel extension and I find are better to remove barrels off used firearms. Always potentially bugger up the cheapest and easiest part to replace. Thus, a dremel (gasp) carefully wielded might be better to remove a crappy $10-15 dollar barrel nut that was loctited than risk messing up the barrel or receiver. You do need a moderately cheap and heavy bench vise to provide insurance against damaging expensive parts. The milsurp tool is junk and the imported ones are even worse. Get something substantial in a wrench or try to borrow one using something like the PMAG or TAPCO ones. You can apply a lot more torque due to increased contact with the barrel nut than you can with three measely pins. Get set of headspace gages no-go and go while you are at it or buy your barrels from a retailer that will headspace a bolt to fit it. Right tools instead of make do usually spares user anguish from a buggered or ruined firearm.

The following is my personal opinion that I have derived from the experience of removing and adding quite a few barrels including the AR, Krag, P14's and 1917 rifles, many Mausers, Springfield 03, and AR's. Most AR 15 barrels are probably overtorqued than what is needed as the range is pretty generous from barely over handtight versus up to about 80 ft lbs. See this old thread https://www.thehighroad.org/index.php?threads/ar-15-barrel-nut-torque.544371/ Unless you are putting a lot of stress on the rifle such as full auto, suppressors, etc., the midrange torque is fine for a new install. However, you might want to go a little higher on the torque on a barrel replacement as threads can loosen but trying to approach 80 can result in damaging the receiver if something slips etc. I use a torque wrench when I am close mainly to slightly tighten and then loosen the nut a couple of times.

I suspect that the reason comes from commercial guns and old milsurps. First, many of these arms have headspace that is affected by a barrel that is not tight enough. Another reason that some milsurp barrels are tight is that the barrels are timed for the front and rear sights. You have a slight timing issue with AR's but nothing like old bolt actions such as a MAS 36. Some are tight because it has had a 50-100 years to rust, bond, be buggered up with screw holes, and generally form a long term relationship with the receiver (Arisakas in particular are a bear to remove). Differering and somewhat damaged threads can also result in barrel tightness. Unless something is wrong with the barrel, I would not loctite them--and such a barrel probably needs to be replaced in an AR unless under emergency conditions. This is my opinion and as usual, YMMV.

Please feel free to roast me over a fire but that is my experience based on messing around rebuilding milsurps for the last eight years or so. I couldn't get ammo to shoot much other than my reloads so I found another timesink for my time. It's been educational and you find out that people like James Howe, Patrick Sweeney, Angier, Gen Hatcher, Gunsmith Kinks, and even specialist web forums such as here with the celebrated and now absent rcmodel.
 
Wheeler or Brownell's clamshell, Geisselles reaction rod, or the PMAG tool all work. I generally use the Brownells clamshell for barrel installation as it supports the receiver (those are pretty fragile) a bit better and it has a gas tube alignment function (those are pretty fragile)
In the course of torquing my first AR barrel recently, I have to say I'm a bit confused about the Reaction Rod's appeal. A similar (home made) tool was used to torque on my actual barrel extension, which makes sense, but I understand that the extensions aren't truly pinned to the barrel by the alignment pin against rotation, but merely secured with loctite.

Now, as with most 'contentious' topics in AR-land, I'm well aware it's not really a problem in practice (and neither is damage to the upper by the alignment pin, generally), but it just struck me as odd that no matter how you secure the barrel/upper to apply torque to the barrel nut, you stress either the 'fragile' upper in torsion, or work to budge the barrel extension while simultaneously transmitting all that torque onto a tiny pin that bears on the upper --seems like you can't win. The real issue appears to be the need for such great torque on fairly delicate parts in the first place, but whatever. (I'm especially confused by Giessele's own description of the RR's advantage in removing barrel nuts on their website; they claim it prevents that alignment pin from bearing into the upper, but isn't the rod the only reason torque would be going through the barrel extension in the first place? For installing a muzzle break the idea makes sense, but not a barrel nut; for that a vise block seems the shortest 'load path' for torque). The RR is certainly more universal, though; I know that no common vise blocks fit my Gibbz side-charging upper, for instance.

Just another of many needless weaknesses/complications to the design. I'd have just threaded the outside of the barrel extension & milled wrench flats onto its rim. And used a big steel helicoil for the mating threads to avoid all this galling worry.

TCB
 
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