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Posted: 10/1/2004 3:54:38 AM EST
My goal is to thread the barrel for my new flash hider. However, in order to get the barrel in my lathe I need to remove it from the upper receiver. I made a tool that is just like the official tool for removing the barrel nut. I'm putting enough torque on the nut that I can see the receiver flexing when I clamp it by the receiver and I can spin the barrel when I clamp the barrel in wooden V-blocks lined with a latex balloon for extra grip. Easily 80+ foot pounds.

After having this much trouble I thought it would be a good time a find other opinions before I wreck something.

Options I've considered so far:

Standing it on end and flooding it with penetrating oil. It looks as if it has grease around these threads so I'm not sure what penetrating oil will gain me.

Heating the nut with the torch. This would be my first choice If there was a way to get the aluminum delta ring off and not destroy the temper of the delta ring spring.

What do you recomend?

Thanks,

Kent
Link Posted: 10/1/2004 6:24:34 AM EST
Buy a Vice Block and clamp the upper in a vice. Or you will risk tweaking the aluminum upper (Anodizing is only surface hardening)


Use a cheater pipe if you have to.
Link Posted: 10/1/2004 6:29:19 AM EST

Originally Posted By Timanator:
Buy a Vice Block



Rarely is there anything better than the right tool for the job.
Link Posted: 10/1/2004 6:40:48 AM EST
[Last Edit: 10/1/2004 6:46:12 AM EST by eddiesar15]

Originally Posted By Green_Canoe:
My goal is to thread the barrel for my new flash hider. However, in order to get the barrel in my lathe I need to remove it from the upper receiver. I made a tool that is just like the official tool for removing the barrel nut. I'm putting enough torque on the nut that I can see the receiver flexing when I clamp it by the receiver and I can spin the barrel when I clamp the barrel in wooden V-blocks lined with a latex balloon for extra grip. Easily 80+ foot pounds.

After having this much trouble I thought it would be a good time a find other opinions before I wreck something.

Options I've considered so far:

Standing it on end and flooding it with penetrating oil. It looks as if it has grease around these threads so I'm not sure what penetrating oil will gain me.
I had a conversation with a gunsmith when I was building my upper,and he happened to mention that he really had a hard time removing a barrel nut on one occasion,if Im not mistaken,it was a DPMS,he eventually had to cut the nut off due to the fact that the barrel nut was installed with no antisieze,I really hope this is not you case
Heating the nut with the torch. This would be my first choice If there was a way to get the aluminum delta ring off and not destroy the temper of the delta ring spring.

What do you recomend?

Thanks,

Kent

I was having a conversation with a gunsmith at the time of me putting my upper together,he happened to mention that he had a real problem removing a barrel nut,i on one occasion if Im not mistaken,it was a DPMS,he eventually had to cut the nut of due to the fact that the barrel nut was assembled with no antisieze,I sure hope that this is not youre case
Link Posted: 10/1/2004 6:50:58 AM EST
Doh! This project was supposed to be cheap and easy. I have the capability to keep it cheap with my labor. Snags like this are why I don't work on cars anymore.

I'm very concerned with the amount of torque this will require. I'm assuming the cheater pipe comment indicates this has happened to you.

I'll make a better block to hold the receiver. Is it correct to assume the action block grips the receiver on the flat below the carrying handle and the front take down pin lug? Leaving the ejection port door untouched.

Kent
Link Posted: 10/1/2004 6:52:32 AM EST
[Last Edit: 10/1/2004 6:53:54 AM EST by Green_Canoe]
Originally Posted By eddiesar15:

I was having a conversation with a gunsmith at the time of me putting my upper together,he happened to mention that he had a real problem removing a barrel nut,i on one occasion if Im not mistaken,it was a DPMS,he eventually had to cut the nut of due to the fact that the barrel nut was assembled with no antisieze,I sure hope that this is not youre case


I see grease around the nut so I am hoping this is not the case.

Kent
Link Posted: 10/1/2004 7:02:12 AM EST
Green, check your IM.
Link Posted: 10/1/2004 9:31:39 AM EST
There is no substitute for a good action block and a good, sturdily mounted vise.

You "make do" tools are your problem, not your upper.
Link Posted: 10/1/2004 10:53:12 AM EST

Originally Posted By A_Free_Man:
There is no substitute for a good action block and a good, sturdily mounted vise.

You "make do" tools are your problem, not your upper.



I've got the vise, The barrel nut tool is nothing more than a plate with pins in it, not to hard to duplicate. I'll grant you an action block would be much better than what I'm using (wooden blocks).

My trepidation comes from the amount of torque I'm able to apply without any sign of movement from the nut. My wrench is 12 inches long and I'm putting 50%+ of my weight (175 lbs) on it before I get my barrel spinning in the v-blocks or see my reciever twisting up. (Not much twisting before I stop, no permanent deformation.)

I'm applying a lot of torque and it is not moving. I'm not so sure as if better tools are the answer or if that just allows me to strip the threads that much faster.

Kent
Link Posted: 10/1/2004 1:07:03 PM EST
I just did a bushmaster and had the torque wrench up to 100 lbs to get the nut off, and even then I had to pump it a few times....but you definitely need the Armor's action clamp and the Heavy duty armorer’s wrench (it's got a 1/2 inch opening for a t wrench) and of course, a securely mounted vice. It's the only thing that's going to let you put that much torque on it without doing bad things to your AR.

btw, for removing barrels, be sure to use the saw-tooth looking side for barrel removal - once again, it's there for super tight nuts like this. The 2 pin or 3 pin side is for putting them on (in my opinion)

Gotta have the right (quality) tools for the job, but once you get them, you'll have them for life.

btw, a friend of mine with a colt had to get his nut cut off...., no, the one on the barrel.
Link Posted: 10/1/2004 1:10:28 PM EST
I wonder if someone used LocTite when they asembled it. In that case, gently applied heat is your friend.
Link Posted: 10/1/2004 1:20:37 PM EST

Originally Posted By MachoNacho:
I just did a bushmaster and had the torque wrench up to 100 lbs to get the nut off,




Tisk tisk, thats a no no...


Never use a torque wrench to remove something thats been bonded metal to metal by heat (Expansion and retraction)


As for improvised Upper Vice lock. I have rigged my own in a pinch once. It does seem to take alot of torque because alot of things are moving(Look carefully as the edges of the upper rotating against anything not properly supported)


Get a Upper vice block. It will safe guarde against a $100 new upper.
Link Posted: 10/1/2004 1:43:05 PM EST
Link Posted: 10/1/2004 1:45:35 PM EST
If it can be arranged Mr. Green_Canoe will pay me a visit, where we will use all the proper tools and see if we can't get this thing off. I'm betting we can.
Link Posted: 10/1/2004 2:24:43 PM EST

Originally Posted By MachoNacho:
I just did a bushmaster and had the torque wrench up to 100 lbs to get the nut off, and even then I had to pump it a few times.....



??????

that poor poor abused tool. send it to me and I'll give it a good home and lots of love and calibrations.....

torque wrenches are for tightening. <- [note the period]

get a vise block (I've even had success recently w/ the "flipper" from DPMS for $35).

rvb
Link Posted: 10/1/2004 2:51:05 PM EST
[Last Edit: 10/1/2004 6:11:30 PM EST by A_Free_Man]
I've got the vise, The barrel nut tool is nothing more than a plate with pins in it, not to hard to duplicate. I'll grant you an action block would be much better than what I'm using (wooden blocks).

My trepidation comes from the amount of torque I'm able to apply without any sign of movement from the nut. My wrench is 12 inches long and I'm putting 50%+ of my weight (175 lbs) on it before I get my barrel spinning in the v-blocks or see my reciever twisting up. (Not much twisting before I stop, no permanent deformation.)

I'm applying a lot of torque and it is not moving. I'm not so sure as if better tools are the answer or if that just allows me to strip the threads that much faster.


This is exactly the problem. You are not using a properly fitting action block.

An action block exactly fits the receiver on the outside, and has an insert that replaces the bolt carrier, which supports it internally. This holds the receiver firmly and safely.

12" of leverage? Man, I use an 18" long breaker bar.

And I use grease, wheel bearing grease (moly grease) like you buy at an auto parts store, and have no problems getting off barrels I put on many, many years before. Don't use neverseize, just grease.

If you don't go see Mongo, contact me for loan of action block. Check your IM.
Link Posted: 10/1/2004 4:21:44 PM EST

torque wrenches are for tightening. <- [note the period]



In general, I know that. the reason I've used it on the first few that I've done is to get an idea of how much it's taking to get these off. It was a recommendation from a friend who is a mechanic so that I could get the a read on what kind of force it was taking to do some of this stuff, and not over-do it or do damage. If this was bad advice, please let me know. Like most who come here, I seek advice from those who know better.

(not to get off topic.., but)..

The army taught me to shoot 'em, and this site and a few friends taught me to build them. I'm open to suggestions, constructive comments can only make me better.
Link Posted: 10/1/2004 4:33:48 PM EST
[Last Edit: 10/1/2004 4:34:33 PM EST by Minuteman419]

Originally Posted By MachoNacho:

torque wrenches are for tightening. <- [note the period]



In general, I know that. the reason I've used it on the first few that I've done is to get an idea of how much it's taking to get these off. It was a recommendation from a friend who is a mechanic so that I could get the a read on what kind of force it was taking to do some of this stuff, and not over-do it or do damage. If this was bad advice, please let me know. Like most who come here, I seek advice from those who know better.

(not to get off topic.., but)..

The army taught me to shoot 'em, and this site and a few friends taught me to build them. I'm open to suggestions, constructive comments can only make me better.



Torque wrenches should only be used when tightening. Break away torque is a different animal.

Regards,

edit, can't speel.

Danny
Link Posted: 10/2/2004 4:19:34 AM EST

Originally Posted By MachoNacho:

torque wrenches are for tightening. <- [note the period]



In general, I know that. the reason I've used it on the first few that I've done is to get an idea of how much it's taking to get these off. It was a recommendation from a friend who is a mechanic so that I could get the a read on what kind of force it was taking to do some of this stuff, and not over-do it or do damage. If this was bad advice, please let me know. Like most who come here, I seek advice from those who know better.

(not to get off topic.., but)..

The army taught me to shoot 'em, and this site and a few friends taught me to build them. I'm open to suggestions, constructive comments can only make me better.



I'm guessing he told you that with the idea that if you know how much torque to get it off, you know how much to get it on with? First problem with that is that you have (or should have) an armor's manual that tells you how much torque you need to put the nut on with (or you could just get it snug, then line up the holes for the gas tube). Secondly, it will almost definately take more torque to remove than tighten.
Link Posted: 10/2/2004 5:25:37 AM EST

I'm guessing he told you that with the idea that if you know how much torque to get it off, you know how much to get it on with? First problem with that is that you have (or should have) an armor's manual that tells you how much torque you need to put the nut on with (or you could just get it snug, then line up the holes for the gas tube). Secondly, it will almost definately take more torque to remove than tighten.




I always put the barrel on according to proper specs - 30 - 35 lbs lbs then tighten to the next aligned hole for the gas tube. The 100 lbs was what it took to get it OFF, definately not ON. Sounds like from what I'm hearing that measuring what it takes to get it off is a useless excersise, though.
Link Posted: 10/2/2004 5:44:19 AM EST
My experience, bending wrenches for a very long time, is that it ALWAYS takes more torque to remove a fastener than to put it on.

If a 250# guy uses a 36" pipe wrench and a 6' cheater pipe to put a nut on, it will take TWO hefty guys and a 10' cheater to take it off. Or a torch. You can count on it. (this was not on a barrel nut!)

100 ft-lb to remove does not at all surprise me, or alarm me, and does not indicate the installer did anything wrong.
Link Posted: 10/2/2004 7:27:34 AM EST
Link Posted: 10/2/2004 10:19:20 AM EST
WOO! HEW! I got it off.

(Please forgive me now.) I cobbled up an action block out of wood and aluminum. Aluminum on the takedown pin lugs, wood on the exterior of the reciever. Then I applied a little heat. So little I'm not sure if it was a factor. (Didn't want to hurt the temper of the delta ring spring.) Then I grit my teeth and leaned into it with all I had. Then something let go. I wasn't sure what I'd wrecked. Then after a 2 second delay to regain composure I found, "Glory be!!! The nut spins with my fingers."

I would have never expected it to take so much force. Very similar to CJ's car story.

Thank you all for your input and offers of help.

Kent
Link Posted: 10/2/2004 10:24:00 AM EST
Glad to hear that. My offer of help stands at any time that you think you might need it. I have all the AR tools you will ever need and there are here to use whenever you need to. Just call or email/IM ahead so that I can set aside time.
Link Posted: 10/2/2004 10:53:31 AM EST
Good to hear you got it off.

IM going to have to disagree with the guys that said to heat it up. If you heat the nut up it will soak right into the threads so fast that I dont see how it will any good. The threads will expand more than the nut will putting more tension between the two. A good way IMO is to freeze the upper in a freezer or even a bucket of ice water if a freezer isnt available. The threads on the upper will shrink more that nut will. The colder the better.
Link Posted: 10/2/2004 11:20:30 AM EST
Thanks for the standing offer Mongo. That further proves what I've known for a long time, " Gun people are some of the nicest around".

On the heating issue... I'm not sure if this is what happens or not but here's my theory: The heat on the steel nut expands the nut. But some is transfered to the aluminum through the threads. The threads have a relatively small contact area when under tension (only one side of the "V" or 50%). The heat that is transfered is conducted fairly rapidly away from the threaded area due to aluminums excellent heat conduction characteristics. Therefor the heat rise in the aluminum at the threads is significantly less than the steel. Hopefully, the temp. difference is of a magnitude that the steel expands more than the aluminum. If I soaked the entire assembly with heat in the oven I agree I would make the fit even tighter.

I considered cooling the receiver while I heated the nut, but I couldn't come up with a method that was easy w/o getting the forward assist and the rear sight full of water.

Kent
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