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Page AR-15 » Build It Yourself
AR Sponsor: bravocompany
Posted: 9/8/2010 6:36:00 AM EDT
Just wondering how many of you are having to torque your barrel to the high end of the torque range? My first few builds were all below 40ft lbs but lately they have all been 70-80ft lbs. Any accuracy or extreme windage adjustments if on the high end?
Link Posted: 9/8/2010 10:10:21 AM EDT
[#1]
Quoted:
Just wondering how many of you are having to torque your barrel to the high end of the torque range? My first few builds were all below 40ft lbs but lately they have all been 70-80ft lbs. Any accuracy or extreme windage adjustments if on the high end?


I had to go 70lbs on my last one I did to get the alignment of nuts notch to the upper for the gas tube to pass through ... no issues as long as your using a barrel clamp and upper block so that your not torque the barrel index pin into the upper causing damage to the upper or barrel. I had this happen once (using just an upper action block) barrel canted when index pin dug into the softer upper threaded area) and didn't realize it till after the hand guards were installed PITA.

ETA spelling
Link Posted: 9/8/2010 10:47:12 AM EDT
[#2]
No idea dont use one. Have to get the notch in the nut centered.
Link Posted: 9/8/2010 11:26:05 AM EDT
[#3]
Quoted:
Just wondering how many of you are having to torque your barrel to the high end of the torque range? My first few builds were all below 40ft lbs but lately they have all been 70-80ft lbs. Any accuracy or extreme windage adjustments if on the high end?


80 ft-lbs is the max.
Link Posted: 9/8/2010 12:19:19 PM EDT
[#4]
Quoted:
No idea dont use one. Have to get the notch in the nut centered.


same! +1
Link Posted: 9/8/2010 2:31:05 PM EDT
[#5]
Tighten 3x s, loosen it,,4th timetighten  till next spoket lines up to install gas tube.
Link Posted: 9/8/2010 6:38:08 PM EDT
[#6]




Quoted:

Tighten 3x s, loosen it,,4th timetighten till next spoket lines up to install gas tube.




This way works like a charm.  +1
Link Posted: 9/9/2010 1:38:10 AM EDT
[#7]



Quoted:





Quoted:

Tighten 3x s, loosen it,,4th timetighten till next spoket lines up to install gas tube.




This way works like a charm.  +1


Ha maybe for you guys. Last time I built with a FF rail I had to dremel the barrel nut so I could get the gas tube where it needed to be. I always seem to need custom work on some of my builds.



 
Link Posted: 9/9/2010 2:41:54 AM EDT
[#8]
Quoted:

Quoted:

Quoted:
Tighten 3x s, loosen it,,4th timetighten till next spoket lines up to install gas tube.


This way works like a charm.  +1

Ha maybe for you guys. Last time I built with a FF rail I had to dremel the barrel nut so I could get the gas tube where it needed to be. I always seem to need custom work on some of my builds.
 


Sometimes it takes tightening MANY times to get the upper and barrel nut to cooperate.  But if you're persistent it usually works pretty well.  It's also important to use a good MIL-G21164 compliant grease when you install the nut, because the torque spec is based on using that kind of grease.  Dry torque, or torquing with a grease of a different composition or viscosity can change the numbers radically.
Link Posted: 9/13/2010 11:13:34 AM EDT
[#9]
Quoted:
Just wondering how many of you are having to torque your barrel to the high end of the torque range? My first few builds were all below 40ft lbs but lately they have all been 70-80ft lbs. Any accuracy or extreme windage adjustments if on the high end?



Still no answers to the questions I asked. Anyone?

Link Posted: 9/13/2010 11:22:50 AM EDT
[#10]



Quoted:



Quoted:

Just wondering how many of you are having to torque your barrel to the high end of the torque range? My first few builds were all below 40ft lbs but lately they have all been 70-80ft lbs. Any accuracy or extreme windage adjustments if on the high end?






Still no answers to the questions I asked. Anyone?





I had one rock river come from the factory that I needed a breaker bar to get loose. It still shot just fine. But I'm not a fan of torquing over 70-80 simply because I'm scared that I might break something.



 
Link Posted: 9/13/2010 11:36:50 AM EDT
[#11]
I've overtorqued one.  The teeth on the barrel nut shear.

I got a better wrench than the GI 3-pin job and was able to continue using that barrel nut.  Works fine.
Link Posted: 9/13/2010 12:43:17 PM EDT
[#12]
Quoted:
Quoted:
Just wondering how many of you are having to torque your barrel to the high end of the torque range? My first few builds were all below 40ft lbs but lately they have all been 70-80ft lbs. Any accuracy or extreme windage adjustments if on the high end?



Still no answers to the questions I asked. Anyone?



I would venture to say that it would vary from build to build, builder to builder. Extreme windage adjustment will result if the barrel is over-torqued so do the obvious thing and, well, don't over-torque.
Link Posted: 9/13/2010 1:14:42 PM EDT
[#13]
Quoted:
Quoted:
Quoted:
Just wondering how many of you are having to torque your barrel to the high end of the torque range? My first few builds were all below 40ft lbs but lately they have all been 70-80ft lbs. Any accuracy or extreme windage adjustments if on the high end?



Still no answers to the questions I asked. Anyone?



I would venture to say that it would vary from build to build, builder to builder. Extreme windage adjustment will result if the barrel is over-torqued so do the obvious thing and, well, don't over-torque.


I would think it would vary as well, which is why I'm asking. Just want to know what torque ranges others are seeing during their builds. Also if any have actually experienced accuracy issues or extreme windage adjustments when on the high end. Not looking for speculation, guessing, or thoughts. Just actual data from other peoples builds.  
Link Posted: 9/13/2010 2:14:32 PM EDT
[#14]
Quoted:
Quoted:

Quoted:

Quoted:
Tighten 3x s, loosen it,,4th timetighten till next spoket lines up to install gas tube.


This way works like a charm.  +1

Ha maybe for you guys. Last time I built with a FF rail I had to dremel the barrel nut so I could get the gas tube where it needed to be. I always seem to need custom work on some of my builds.
 


Sometimes it takes tightening MANY times to get the upper and barrel nut to cooperate.  But if you're persistent it usually works pretty well. It's also important to use a good MIL-G21164 compliant grease when you install the nut, because the torque spec is based on using that kind of grease.  Dry torque, or torquing with a grease of a different composition or viscosity can change the numbers radically.



+1 I think this is one of the most overlooked steps in an upper build.
Link Posted: 9/13/2010 2:39:53 PM EDT
[#15]
I've never had a nut hit 70ft-lbs to line up. The most I can recall was a Citadel A1 barrel on an RRA A2 upper which lined up at 64ft-lbs, but the others have all been well below 50ft-lbs. The last two I did were a Colt socom barrel on colt M4 upper set at 36ft-lbs and the Daniel Defense M4 barrel I put on my Vltor MUR upper last night torqued at 41ft-lbs.

There might be some kind of relation between manufacturer tolerances to be found, but I've done nowhere near enough assemblies to figure them out.
Link Posted: 9/13/2010 5:17:19 PM EDT
[#16]
Quoted:

Quoted:
Quoted:
Just wondering how many of you are having to torque your barrel to the high end of the torque range? My first few builds were all below 40ft lbs but lately they have all been 70-80ft lbs. Any accuracy or extreme windage adjustments if on the high end?



Still no answers to the questions I asked. Anyone?


I had one rock river come from the factory that I needed a breaker bar to get loose. It still shot just fine. But I'm not a fan of torquing over 70-80 simply because I'm scared that I might break something.
 
The amount of effort to remove a barrel nut that's been on a while is not really related to the amount of torque applied at the beginning.  I've found this out with my own builds.  I think the longer it's been together (and the more rounds through it), the harder it will be to loosen the barrel nut.
Link Posted: 9/13/2010 5:52:32 PM EDT
[#17]
I just put a 1inch impact gun on it with 150 psi pushing it and start rattling.
Link Posted: 9/13/2010 6:12:33 PM EDT
[#18]
The correct and proper torque range is 30 to 80.I torque all mine to 50 and they always wind up either dead balls lined up or just need a tiny tweek tighter to line up.
Page AR-15 » Build It Yourself
AR Sponsor: bravocompany
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