Torque spec on castle nut *HELP I oopsed*

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[ARCHIVED THREAD] - Torque spec on castle nut *HELP I oopsed*

Posted: 12/13/2010 7:51:51 AM EDT

I know this has been hashed out over and over again but I am looking for the correct answer.

I have built a few lowers over the years and have seen where you are supposed to torque to 40 in/lb but have also seen 40 ft/lb. When I built my A2 stocked rifle I torqued to 36 ft/lb and it has held.

However, a few months back I built an M4 stocked lower and torqued the castle nut to 15 ft/lb just like 3 others but this one came loose and is now relying on the staking to keep it in place. I will be fixing it at some point as it isn't my go to rifle but I wonder which is correct? 40 ft/lb is a LOT of torque on the lower even with the Brownells magazine vise block and I worry about messing it up.

Also, in order to undo the staking do I just loosen the nut and it will break it or do I have to drill it or something?

Posted: 12/13/2010 8:12:01 AM EDT

[#1]

according to the maintenance manual I have the torque spec for the castle nut is 40 (+/- 2) inch-pounds

Posted: 12/13/2010 8:18:07 AM EDT

[#2]

Quoted:
according to the maintenance manual I have the torque spec for the castle nut is 40 (+/- 2) inch-pounds

That is a misprint as point out.
I use loctite and clamp the lower as close to the buffer tube as possible. I go hand tight and call it good.

Posted: 12/13/2010 8:22:30 AM EDT

[#3]

Quoted:

Quoted:
according to the maintenance manual I have the torque spec for the castle nut is 40 (+/- 2) inch-pounds

That is a misprint as point out.
I use loctite and clamp the lower as close to the buffer tube as possible. I go hand tight and call it good.

I guess you're right...
next page says 40ft/lbs about the M16 RE...I've also checked the Diemaco Tach Manual and it says 40 ft/lbs for both the M4 and M16

ETA:
OP sorry for the wrong info on my earlier post

Posted: 12/13/2010 8:25:29 AM EDT

[#4]

40 ft lbs.

For those if you that go hand tight...

Pin your lower between your knees, and with the stock on, torque the tube lefty loosy.

20 bucks says you move it. Those things need torque, or they will come loose.

Posted: 12/13/2010 8:28:15 AM EDT

[#5]

no need to torque it. snug it up and stake it. there is no way it can come loose if it's installed correctly.

Posted: 12/13/2010 8:28:35 AM EDT

[#6]

Thanks for all the help. I will do it to 40 ft/lbs. I have a 600 in/lb Snap-On torque wrench I will use as it should be more accurate than a 20-100 ft/lb torque wrench.

Quoted:
40 ft lbs.

For those if you that go hand tight...

Pin your lower between your knees, and with the stock on, torque the tube lefty loosy.

20 bucks says you move it. Those things need torque, or they will come loose.

I noticed that even when tightening to 15 ft/lb. That is actually how I noticed this one was loose. 40 ft/lb just seems like a helluva lot of torque on the receiver.

Posted: 12/13/2010 9:31:44 AM EDT

[#7]

So I took the old one off easily and went to put the new one on. Evidentally the Vltor castle nut isn't of horribly high quality as when I got to 33 ft/lbs the slot gave way and bent. I was using the Brownells buttstock wrench is gtg but I'm sorta pissed right now.

It is still serviceable but it doesn't look good. I staked it and will run it like that for now until I can get a new one.

At one time I saw a wrench that slid over the receiver extension and was a complete circle with 2 tabs on it. Does anyone know who made that one?

Posted: 12/13/2010 9:44:26 AM EDT

[#8]

I put my lower in a vise (using a mag vise block of course), apply a little blue locktite, and use my spanner wrench to ensure the castle nut is tight. I use some elbow grease, but I don't go all hell on it. And if I feel it's necessary (which I usually do just because), I stake the end plate and castle nut.

Posted: 12/13/2010 9:50:21 AM EDT

[#9]

Quoted:
So I took the old one off easily and went to put the new one on. Evidentally the Vltor castle nut isn't of horribly high quality as when I got to 33 ft/lbs the slot gave way and bent. I was using the Brownells buttstock wrench is gtg but I'm sorta pissed right now.

It is still serviceable but it doesn't look good. I staked it and will run it like that for now until I can get a new one.

At one time I saw a wrench that slid over the receiver extension and was a complete circle with 2 tabs on it. Does anyone know who made that one?

http://www.hammerheadrifletool.com/HammerHead_Rifle_Tool/HammerHead_Rifle_Tool_Home.html

theres one...

Posted: 12/13/2010 10:18:22 AM EDT

[#10]

Thanks for the link.

I wonder if it is user error as I have to put a 1/2" adapter on the torque wrench so I wonder if I am canting it somehow???

Here is what I did to it. Any thoughts...should I change it? I used Aeroshell 33MS grease and just decided to stake it as I won't be able to get another end plate or castle nut for awhile

Posted: 12/13/2010 10:32:01 AM EDT

[#11]

File or stone the edges of the buggered up slot,,,,hit it with cold blue.

Good enough until you really need to swap it out.

Posted: 12/13/2010 10:37:19 AM EDT

[#12]

Quoted:
I put my lower in a vise (using a mag vise block of course), apply a little blue locktite, and use my spanner wrench to ensure the castle nut is tight. I use some elbow grease, but I don't go all hell on it. And if I feel it's necessary (which I usually do just because), I stake the end plate and castle nut.

Same here, but I always stake my castle nuts.

Even with the blue loctite, disassembly has never been a problem.

I have never bothered to use a torque wrench for that.

Posted: 12/13/2010 3:21:32 PM EDT

[#13]

Quoted:
Thanks for the link.

I wonder if it is user error as I have to put a 1/2" adapter on the torque wrench so I wonder if I am canting it somehow???

Here is what I did to it. Any thoughts...should I change it? I used Aeroshell 33MS grease and just decided to stake it as I won't be able to get another end plate or castle nut for awhile
http://i229.photobucket.com/albums/ee30/jlficken/Oops.jpg

You dont need to use grease on the buffer tube/castle nut. Use blue locktite. Every tech manual, armoror videos, etc that I have seen said to use some form if thread-locker

Posted: 12/13/2010 3:42:06 PM EDT

[#14]

Snug it up by hand (no torque wrench) and stake it. It wont go anywhere. Your over thinking a simple task.

Posted: 12/13/2010 7:49:37 PM EDT

[#15]

40 foot pounds is the correct answer. Those are the spec guidelines from Colt. Inch pounds was a typo.
I've torqued all mine to 40 foot pounds and then stake it. Don't ever use loctite on the castle nut, thats the hack/slap job way of doing it.

Posted: 12/13/2010 7:58:29 PM EDT

[#16]

Quoted:
File or stone the edges of the buggered up slot,,,,hit it with cold blue.

Good enough until you really need to swap it out.

Peen it down into place rather than removing all that steel - you might need to put a tool on it again some day.

Posted: 12/13/2010 8:14:35 PM EDT

[#17]

Quoted:
40 foot pounds is the correct answer. Those are the spec guidelines from Colt. Inch pounds was a typo.
I've torqued all mine to 40 foot pounds and then stake it. Don't ever use loctite on the castle nut, thats the hack/slap job way of doing it.

Yup.

Posted: 12/13/2010 10:05:16 PM EDT

[#18]

Quoted:
no need to torque it. snug it up and stake it. there is no way it can come loose if it's installed correctly.

This is not even close to true.

These things need to be torqued.

It amazes me how many people are saying "just tighten it".

The things will come loose and if you put any torque on your stock, it will move the entire assembly.

Don't believe me? As I stated before, put the lower between your knees and crank on your stock.

Posted: 12/14/2010 12:01:46 AM EDT

[#19]

The way I tighten the castle nut is to clamp the bare receiver across the solid part near the rear in a leather padded vise. I lube the threads with a good EP oil; I use Weaponshield. I tighten the nut as tight as I can with the RRA type wrench (about 7" long - 40'# = 80# on the wrench) three times to seat the threads and then one final effort to get it as tight as I can. Then I stake it. When I have had to take these apart it takes an extension on the wrench to break them loose after the staking has been removed with a burr.

Seating the threads is important IMO as is lubrication on the threads. Tightening a lubricated threaded connection allows a much tighter connection for a given amount of torque than dry. In the engineering world a torque spec means nothing without specifying the lube condition of the threads.

A properly seated and torqued castle nut does not require Loctite.

Posted: 12/14/2010 2:59:49 AM EDT

[#20]

Quoted:

Quoted:
no need to torque it. snug it up and stake it. there is no way it can come loose if it's installed correctly.

This is not even close to true.

These things need to be torqued.

It amazes me how many people are saying "just tighten it".

The things will come loose and if you put any torque on your stock, it will move the entire assembly.

Don't believe me? As I stated before, put the lower between your knees and crank on your stock.

so why don't most stock wrenches "Spikes for example" come with a cutout for a torque wrench?

Posted: 12/14/2010 4:49:03 AM EDT

[#21]

Quoted:

Quoted:
no need to torque it. snug it up and stake it. there is no way it can come loose if it's installed correctly.

This is not even close to true.

These things need to be torqued.

It amazes me how many people are saying "just tighten it".

The things will come loose and if you put any torque on your stock, it will move the entire assembly.

Don't believe me? As I stated before, put the lower between your knees and crank on your stock.

so why don't most stock wrenches "Spikes for example" come with a cutout for a torque wrench?

Are you seriously trying to justify your statement with the fact that some brands of tools aren't designed to accept a torque wrench? If it didn't need to be torqued, there wouldn't be a torque spec for it. The proper tool has the hole for a torque wrench.

Posted: 12/14/2010 5:22:43 AM EDT

[#22]

Thanks for all of the replies guys.

I refuse to use loctite on this part. I did it once and didn't like the results.

There is a reason that there are torque specifications and I want to follow them.

The wrenches that don't have a torque wrench hole in them are either only meant for taking the nut off or are incorrectly designed.

I did find out after investigating last night what happened. The pin in my wrench turned allowing the wrench to slip off of the slot. It did not hurt the threads it only moved a little bit of metal towards the top of the slot which I won't be using until I go to remove the nut and even then I will be putting pressure on the opposite side of the slot.

Posted: 12/14/2010 8:07:39 AM EDT

[#23]

Quoted:
I refuse to use loctite on this part. I did it once and didn't like the results.

At work we use Permabond HM118 Threadlocker. High strengh and melts at approx. 200° F. Pour boiling water on it or use a mini butane torch and the fastner comes right off.

Posted: 12/14/2010 8:13:27 AM EDT

[#24]

Quoted:

Quoted:
no need to torque it. snug it up and stake it. there is no way it can come loose if it's installed correctly.

This is not even close to true.

These things need to be torqued.

It amazes me how many people are saying "just tighten it".

The things will come loose and if you put any torque on your stock, it will move the entire assembly.

Don't believe me? As I stated before, put the lower between your knees and crank on your stock.

so why don't most stock wrenches "Spikes for example" come with a cutout for a torque wrench?

Are you seriously trying to justify your statement with the fact that some brands of tools aren't designed to accept a torque wrench? If it didn't need to be torqued, there wouldn't be a torque spec for it. The proper tool has the hole for a torque wrench.

please link the "proper" tool please since Spikes is using the wrong one. all i'm saying is i tightened mine and it does not move at all. you people and your "specs"

hell why stake it if it is torqued to specs? should it still come loose after 40 lbs of torque?

Posted: 12/14/2010 8:21:40 AM EDT

[#25]

Quoted:

Quoted:
I put my lower in a vise (using a mag vise block of course), apply a little blue locktite, and use my spanner wrench to ensure the castle nut is tight. I use some elbow grease, but I don't go all hell on it. And if I feel it's necessary (which I usually do just because), I stake the end plate and castle nut.

Same here, but I always stake my castle nuts.

Even with the blue loctite, disassembly has never been a problem.

I have never bothered to use a torque wrench for that.

Agreed and agreed, same here. Blue loctite and elbow grease, add a stake, call it good. Loctite won't come free without heat.

Posted: 12/14/2010 8:35:57 AM EDT

[#26]

I'm not sure if anyone else noticed this, but if 40 in-lb was a misprint, did anyone bother to submit a 2028 to correct the TM?

As I recall, the carbine castle nut is not the same as the rifle buffer tube. The buffer tube is a 1 piece deal, if you turn the stock, you could theoretically untighten the tube, so it should be torqued down properly and there are tools to do this.

However, the carbine castle nut works a bit differently. Turning the buffer tube doesn't necessarily turn the castle nut. The buffer tube is aligned to the spring retainer, so if you cranked it hard with the lower locked down in a bench vise, you'd push the against that retainer.

Posted: 12/14/2010 9:03:26 AM EDT

[#27]

Quoted:

Quoted:
no need to torque it. snug it up and stake it. there is no way it can come loose if it's installed correctly.

This is not even close to true.

These things need to be torqued.

It amazes me how many people are saying "just tighten it".

The things will come loose and if you put any torque on your stock, it will move the entire assembly.

Don't believe me? As I stated before, put the lower between your knees and crank on your stock.

so why don't most stock wrenches "Spikes for example" come with a cutout for a torque wrench?

Are you seriously trying to justify your statement with the fact that some brands of tools aren't designed to accept a torque wrench? If it didn't need to be torqued, there wouldn't be a torque spec for it. The proper tool has the hole for a torque wrench.

please link the "proper" tool please since Spikes is using the wrong one. all i'm saying is i tightened mine and it does not move at all. you people and your "specs"

hell why stake it if it is torqued to specs? should it still come loose after 40 lbs of torque?

I use the Hammer Head rifle tool. Click Here
I get a clean torque everytime, not a fudged up castle nut like in the picture above. I just attach a torque wrench into the proper hole on the tool, crank to 40 foot pounds, stake and done.
Always do this with a vice block attached to your lower receiver, and then the vice block in a vice. It's a the best way to do a clean job.

Posted: 12/14/2010 9:16:48 AM EDT

[#28]

Quoted:
Thanks for the link.

I wonder if it is user error as I have to put a 1/2" adapter on the torque wrench so I wonder if I am canting it somehow???

Here is what I did to it. Any thoughts...should I change it? I used Aeroshell 33MS grease and just decided to stake it as I won't be able to get another end plate or castle nut for awhile
http://i229.photobucket.com/albums/ee30/jlficken/Oops.jpg

I think it's the tool you are using. If it's a standard castle nut tool, all the force is being applied to one side of the nut, which can cause the wrench to slip.
The link I posted above for the Hammer Head rifle tool addresses this issue by having applied force to all sides of the castle nut. Therfore giving you no slip or ugly torque marks on your castle nut.

Posted: 12/16/2010 10:34:27 AM EDT

[#29]

Quoted:

Quoted:
no need to torque it. snug it up and stake it. there is no way it can come loose if it's installed correctly.

This is not even close to true.

These things need to be torqued.

It amazes me how many people are saying "just tighten it".

The things will come loose and if you put any torque on your stock, it will move the entire assembly.

Don't believe me? As I stated before, put the lower between your knees and crank on your stock.

so why don't most stock wrenches "Spikes for example" come with a cutout for a torque wrench?

Are you seriously trying to justify your statement with the fact that some brands of tools aren't designed to accept a torque wrench? If it didn't need to be torqued, there wouldn't be a torque spec for it. The proper tool has the hole for a torque wrench.

please link the "proper" tool please since Spikes is using the wrong one. all i'm saying is i tightened mine and it does not move at all. you people and your "specs"

hell why stake it if it is torqued to specs? should it still come loose after 40 lbs of torque?

I agree with the torque wrench method. I didn't torque my first lower castle nut and went just over hand tight with my DPMS wrench. After a few months I could twist my stock a few degrees either way and the only thing stopping me from twisting the stock assembly copletely out was the nub in the end plate. (which was staked) I bought a torque wrench reassembled everything again (with bearing grease) and the slot went about a 1/2" past where I staked it the first time. I didn't stake it again but witness marked it with paint and after months of shooting it hasn't moved.

Edited: grammar

Posted Via AR15.Com Mobile

Posted: 12/16/2010 3:04:31 PM EDT

[#30]

"Are you seriously trying to justify your statement with the fact that some brands of tools aren't designed to accept a torque wrench? If it didn't need to be torqued, there wouldn't be a torque spec for it. The proper tool has the hole for a torque wrench."

Wheel lug nuts have a torque specification but ALL the lug nut wrenches (cross pattern) I've ever used do not have any way to connect a torque wrench. Plus I don't think that I've ever torqued a lug nut ... and guess what, never had one come loose.

Posted: 12/16/2010 3:14:32 PM EDT

[#31]

Quoted:
"Are you seriously trying to justify your statement with the fact that some brands of tools aren't designed to accept a torque wrench? If it didn't need to be torqued, there wouldn't be a torque spec for it. The proper tool has the hole for a torque wrench."

Wheel lug nuts have a torque specification but ALL the lug nut wrenches (cross pattern) I've ever used do not have any way to connect a torque wrench. Plus I don't think that I've ever torqued a lug nut ... and guess what, never had one come loose.

Good for you. This has nothing to do with the thread.

Most people overtorque the lug nuts on their vehicles which is why they don't come loose. Any time I rotate my tires or do my brakes, etc I use a proper torque wrench to put the lug nuts back on. Undertorquing can result in the wheel coming loose, overtorquing can damage the aluminum wheel. But do whatever you want, it's your stuff. Just remeber there is a right way and a wrong way to do thngs. Just because you've never had an issue, doesn't mean you are doing it right.

[ARCHIVED THREAD] - Torque spec on castle nut *HELP I oopsed*

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