To Torque or Not to Torque?

[Steel head]

Yes. Makes sense and I agree. I was just theorizing off of what I just learned about, however I do know of some who really do cut barrels and chambers for hand tight only applications. Cant say I agree, but it is a thing. I guess my real point in my previous post was to find out if the .002 bump on the brass was such a big deal that if they wanted to start shooting hand tight would they need to account for it. I wouldn't doubt it would be safe enough, just trying to figure out the reloading concepts before I start.

It’s generally a non issue
That .001-.002 will add to initial stretch on first firing.
If you reload and want brass to last I always try to keep initial stretch below .005 and then bump shoulders .001-.002 and all is good.
If your just shooting factory ammunition .005-.010 case stretch isn’t optimal but totally safe.

I set my chambers to or less than .002 over new case length because I like brass to imitate the energizer bunny

 

[carbonbased]

I usually do 100 lb-ft on barrels and 50 lb-ft on Savage barrel nuts. If the thread fit is good, I have not observed any change in headspace between this and "hand tight". In fact, a properly-fitted barrel basically doesn't rotate once it's snug, even if the threads are lubricated. A bolt of the same size would be torqued to well over 600 lb-ft, so it's not like any appreciable stretch is generated with a measly 100 lb-ft.

Breaking loose factory barrels from both Remington and Savage is a different story, and should not be used as a reference point for installing a quality aftermarket barrel.



You're mistaking the force generated with hand grip (which should be well above 100 lb for a healthy adult male) with the torque required to install a barrel. These are not the same things; they are in fact remarkably different. If you want to determine the torque that can be generated, an estimate can be calculated by multiplying one's grip strength by the coefficient of friction between skin and the barrel (or barrel nut), and then multiplying that by the barrel (or nut) diameter. This will not come out anywhere close to 100 lb-ft, which is immediately obvious to anyone who has ever employed basic hand tools.

Hey pal, speak for yourself. I've measured my barrel-installing hand torque to max out at 101 ft-lbs.

When removing barrels I really have to take 'er easy or I will crush the barrel with my bear hands.

In fact, I have a 308 barrel that I accidentally crushed down to 17HMR. Still hammers tho' @ .25MOA if I do my part breaks like a glass rod.

 

[Jscb1b]

Do you double click your barrel installing bear paws or just grunt?

 

[King_beardsly]

I now use the ugga dugga system of precision torque

 

[Baron23]

ACR says 100 ft/lbs (no greater than 150 ft/lbs) for the CDG. Just another data point.

 

[carbonbased]

Do you double click your barrel installing bear paws or just grunt?

Rrrwwaaarrrr!!!

 

[pavementends]

All these posts about calibration and no one has mentioned it is only correct in a climate controlled environment or the fact that the calibration techs can neither read nor do math. Farmer tight is where it is at! I use 75 ft lbs for either shouldered or barrel nut.

 

[supercorndogs]

Hey pal, speak for yourself. I've measured my barrel-installing hand torque to max out at 101 ft-lbs.

When removing barrels I really have to take 'er easy or I will crush the barrel with my bear hands.

In fact, I have a 308 barrel that I accidentally crushed down to 17HMR. Still hammers tho' @ .25MOA if I do my part breaks like a glass rod.

I once grabbed a 1 on 14 twist 22-250 barrel by both ends and twisted it into a 1 on 7.

 

[Boatninja]

The snap thing was mentioned but I’m not sure what that is exactly. Seems like it might be a quick hit with something or the palm of the hand.

One good whack with a rubber hammer

 

[Boatninja]

I put a PVA shouldered barrel on a ARC CDG and on a witness mark it never moved between 45 and 70 Ft Lbs I couldn't see the point in stressing things beyond that. 7th - 10th break in rounds made perfect holes touching clover leaf. Threads were dressed very sparingly with silver never seize.

 

[carbonbased]

I once grabbed a 1 on 14 twist 22-250 barrel by both ends and twisted it into a 1 on 7.

We are fellow bears with bear paws of death, you and I.

 

[Raffy]

You know, I am really liking where this thread is going! Bear Arms fo Life!!!

 

[bobb3950]

Just a quick comment.
With bolt action barrels, I torque to 60 ft lbs.
With AR style, I tighten the barrel nut as tight as I can by hand, then, gently, smack it once with a rubber mallet.
Seems to work every time and have had no problems at all.

 

[Tokay444]

The more the better. My minimum is 150ft/lbs on shouldered centerfire barrels.

 

[XLR308]

Just a quick comment.
With bolt action barrels, I torque to 60 ft lbs.
With AR style, I tighten the barrel nut as tight as I can by hand, then, gently, smack it once with a rubber mallet.
Seems to work every time and have had no problems at all.

 

[LeftyJason]

I once grabbed a 1 on 14 twist 22-250 barrel by both ends and twisted it into a 1 on 7.

Shoulda made it a gain twist.

 

[kthomas]

The more the better. My minimum is 150ft/lbs on shouldered centerfire barrels.

What difference do you notice between say 75 ft-lbs and 150 ft-lbs of torque?

I used to torque all my barrels to 100 ft-lbs, but now have arbitrarily decided to torque them to 75. I don't notice any practical difference.

 

[parshal]

I do all mine at 80 now (used to be 100) and have thought about going to 65-70 simply for ease of removal in my 419 vs having to use the Brownells heavy duty vise.

 

[Tokay444]

What difference do you notice between say 75 ft-lbs and 150 ft-lbs of torque?

I used to torque all my barrels to 100 ft-lbs, but now have arbitrarily decided to torque them to 75. I don't notice any practical difference.

Better precision, and more repeatable zero when I pull barrels for cleaning. When guys like Ian Kelbly, Ted Karagias, and Mike Rescigno speak, I pay attention.

 

[oldrifleman]

You pull your barrel to clean it???

 

[Tokay444]

You pull your barrel to clean it???

Often.

 

[hero's machine]

I encourage all browning abolts to be applied with 150# and lube.

That 32tpi makes it spin until it touches the mag box.

 

[oldrifleman]

Often.

I am more of a spin it on and shoot it till it’s not a keeper anymore. Then it becomes a tomato stake and is replaced by something new. I torque them to 75.

 

[kthomas]

Better precision, and more repeatable zero when I pull barrels for cleaning. When guys like Ian Kelbly, Ted Karagias, and Mike Rescigno speak, I pay attention.

I do know that Mike torques his barrels up much higher than 150 ft-lbs, and I believe he uses a buttress thread to do so. The torque he achieves is not practically attainable on a typical custom action.

However I'm unaware of what Kelbly and Ted have to say about the manner.

 

[Tokay444]

Ian says 150lb/ft minimum and Ted says the more the better, but over 100 at an absolute minimum. The threads can take well in excess of 1000ft/lbs.

 

[XLR308]

Ian says 150lb/ft minimum and Ted says the more the better, but over 100 at an absolute minimum. The threads can take well in excess of 1000ft/lbs.

I went with 110 ft lbs at the recommendation from Kelblys.
Used a Snap-on digital Tech-Wrench to torque and have a long Snap-on 1/2" breaker bar for removal.

 

[Rio Precision Gunworks]

You pull your barrel to clean it???

It's much easier to clean when it's not in the stock chassis and when the action is off. Less stuff to work around and you can plug the muzzle and soak it if you want.

As long as you have a proper barrel vice, the amount of time it takes to take off/put on is trivial.

 

[reelserious]

i used to be an over torquer but after seeing my friends with their quick change barrels going with just over hand tight I have decided on 75 FTlbs.

not as much as Remington with their 100+ and loctite, LOL but I think 75 is just about right.

 

[308pirate]

Anyone who talks about "thread crush" is repeating nonsense bullshit and can be safely ignored.

 

[XLR308]

Anyone who talks about "thread crush" is repeating nonsense bullshit and can be safely ignored.

I am of the same mindset when it comes the the degree of precision that properly cut barrel tennon threads are mated to the reciever when properly executed.
Not like bin quality nuts and bolts.

 

[308pirate]

I am of the same mindset when it comes the the degree of precision that properly cut barrel tennon threads are mated to the reciever when properly executed.
Not like bin quality nuts and bolts.

The quality or fit of threads is irrelevant.

Thread crush doesn't exist and anyone who claims it does is welcome to present a paper proving it to ASME.

 

[XLR308]

The quality or fit of threads is irrelevant.

Thread crush doesn't exist and anyone who claims it does is welcome to present a paper proving it to ASME.

By thread crush are you referring to the threads mating as in male to female thread due to pressure from the torque process ?

 

[oldrifleman]

It's much easier to clean when it's not in the stock chassis and when the action is off. Less stuff to work around and you can plug the muzzle and soak it if you want.

As long as you have a proper barrel vice, the amount of time it takes to take off/put on is trivial.

I guess if I were to go that direction the Zues action would be the way to go. It would be tough to use my barrel vise with a large optic still mounted. I just resist taking optics and stuff off the rifle on a regular basis. I do acknowledge the benefits though if a deep cleaning is required.

 

[308pirate]

By thread crush are you referring to the threads mating as in male to female thread due to pressure from the torque process ?

I couldn't tell you what the uneducated doofuses who talk about thread crush mean because it's a term that has no meaning among professionals.

Threads mate the second they come in contact with one another.

Fastener tension is not generated by threads crushing or deforming or anything else. That's threads stripping or galling or deforming aka joint failure.

Tension is generated when the fastener body stretches as threads advance and the head is stationary. The strain/angle diagram explains it all.

 

[XLR308]

I couldn't tell you what the uneducated doofuses who talk about thread crush mean because it's a term that has no meaning among professionals.

Threads mate the second they come in contact with one another.

Fastener tension is not generated by threads crushing or deforming or anything else. That's threads stripping or galling or deforming aka joint failure.

Tension is generated when the fastener body stretches as threads advance and the head is stationary. The strain/angle diagram explains it all.

Just wanted some clarification I thought maybe I was missing something.
Still haven't had breakfast and thought I was looking for a problem to a solution.

 

[308pirate]

Still haven't had breakfast

You and me both. But I've had coffee.

 

[XLR308]

You and me both. But I've had coffee.

I don't drink coffee so I'm a fool in the morning without food.

 

[Tokay444]

i used to be an over torquer but after seeing my friends with their quick change barrels going with just over hand tight I have decided on 75 FTlbs.

not as much as Remington with their 100+ and loctite, LOL but I think 75 is just about right.

You’ll never be able to over torque a 1-1/16” thread. Ever.

 

[Tokay444]

I guess if I were to go that direction the Zues action would be the way to go. It would be tough to use my barrel vise with a large optic still mounted. I just resist taking optics and stuff off the rifle on a regular basis. I do acknowledge the benefits though if a deep cleaning is required.

No.

 

[oldrifleman]

No.

Not sure what you mean by no, but I never posed a question. But I do feel that beyond a certain point continued tightening is pointless. As a Mechanical engineer I am not sure what I am searching for with Torque values over 75-85 lb/ft.

 

[Tokay444]

Not sure what you mean by no, but I never posed a question. But I do feel that beyond a certain point continued tightening is pointless. As a Mechanical engineer I am not sure what I am searching for with Torque values over 75-85 lb/ft.

Your barrel is a critical fastener.

 

[oldrifleman]

Yes it is, as is an engine head bolt (normally 25-35lb/ft). The recommended torque value for a critical fastener is based on yield strength of the materials (65-75% is nominal). It is normally defined by the designer. In my case Impact Precision specifies approximately 72 lb/ft. I think I will believe them as I have not done the materials analysis of both barrel steel and the 737r action materials.

 

[Tokay444]

You do you. As an ME, I’m sure you’ll work it out. Hint: it’s over 10x72.
My head screw torque procedure is 5 steps, which end up WELL in excess of 35ft/lbs.
Step 1: 3-11 Nm (27-97 in-lbf)
Step 2: 13-17 Nm (116-150 in-lbf)
Step 3: 43-47 Nm (32-34 ft-lbf)
Step 4: 88°-92°
Step 5: 88°-92°

 

[308pirate]

You’ll never be able to over torque a 1-1/16” thread. Ever.

Well......not with ordinary tools

 

[Tokay444]

Well......not with ordinary tools

Right. Like the stuff that’s sold with the specific intend of barrel changes.

 

[oldrifleman]

And used by some shade tree mechanics to exceed manufactures design recommendations.

 

[Tokay444]

And used by some shade tree mechanics to exceed manufactures design recommendations.

Which manufacturer design recommendations?

 

[oldrifleman]

Impact precision who specify 72lb/ft for the Barrel torque value

 

[Tokay444]

I’ll ask Tate why next time I’m talking to him.

 

[Tokay444]

I’m certain it isn’t because the action is too weak to take more.