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rckjeep
01-05-2011, 9:58 PM
I'm trying to replace my Delta ring, spring and snap ring. I cut it off to install a free float rail. Now I'd like to put my AR on a diet and run the Magpul handguard. That's the backstory, here's the issue.

I removed the upper, knocked out the front site pins, site and gas tub. A buddy has the upper reciever vise clamp which we used to hold the upper to remove the barrel nut. We used an AR tool attached to a 1/2" drive rachet to add some leverage to no resolve. We then tried a torque wrench to measure how tight it was and it was still not budging at 80 ft lbs. We tried some penetrating oil and a little heat without any luck. Does anyone have any advise?

freonr22
01-05-2011, 10:43 PM
btw never use a torque wrench for loosening. imho, nut is torque 70-110ft/lbs? somewhere in there..

ccwtrainer
01-05-2011, 11:08 PM
I am a certified AR Armorer. You are correct with your assessment of 80ft/lbs. The proper torque setting for AR barrel nuts is 30 to 80ft/lbs.

Sometimes beefcakes that work at manufacturers decide to use way to much torque when assembling these. I have had to really crank on some in the past to get many parts loose, including barrel nuts, flash suppressors, and especially gas block taper pins!

It sounds like you're doing everything right. I know that you feel weary about using more torque but, there's really nothing else you can do. I personally would add a little more oil, re-heat it and go for it. Just make sure that the upper is fully secured in a well secured vise, that your wrench is fully seated in the barrel nut and that you're wearing eye protection. Eventually something's gotta give ... hopefully it's the barrel nut. Good luck bro!

rckjeep
01-06-2011, 8:46 AM
I am a certified AR Armorer. You are correct with your assessment of 80ft/lbs. The proper torque setting for AR barrel nuts is 30 to 80ft/lbs.

Sometimes beefcakes that work at manufacturers decide to use way to much torque when assembling these. I have had to really crank on some in the past to get many parts loose, including barrel nuts, flash suppressors, and especially gas block taper pins!

It sounds like you're doing everything right. I know that you feel weary about using more torque but, there's really nothing else you can do. I personally would add a little more oil, re-heat it and go for it. Just make sure that the upper is fully secured in a well secured vise, that your wrench is fully seated in the barrel nut and that you're wearing eye protection. Eventually something's gotta give ... hopefully it's the barrel nut. Good luck bro!

Thanks a ton, I'll head back over to my buddies with all the smithing tools and we'll do just what you suggest. We were worried about damaging the upper.

Very true you should never use a torque wrench to loosen something. We used it to check the torque. Which still may not be smart but I let my garage gunsmith/engineer do the work. I trust him, plus it's his garage. Thanks for the tip though.

donking
01-06-2011, 11:23 AM
I've read that sometimes you need to let the penetrating oil do its job for a few days and then try again.

ccwtrainer
02-21-2011, 10:20 PM
Thanks a ton, I'll head back over to my buddies with all the smithing tools and we'll do just what you suggest. We were worried about damaging the upper.

Very true you should never use a torque wrench to loosen something. We used it to check the torque. Which still may not be smart but I let my garage gunsmith/engineer do the work. I trust him, plus it's his garage. Thanks for the tip though.

How did everything work out?

If you can, post a pic or two of the end result.