Torque Recomendations

[Clark]

You start with the screw rating.
You discount torque proportionally % for female engagement less than 1.5 times the root [the root is the minor diameter of the screw thread].
You discount torque for lube; 0% for dry, ~ 25% for oil or grease, and ~50% for wax.

For scope mount screws max torque is is often higher for the front screws [more female engagement] vs the back screws.

Empirical verification:
Mill some metal as thick as your receiver. Drill and tap. Clean out the tap magic and then lube as you would in the rifle. Torque until the female strips out. Discount that torque by a safety margin.

 

[ARKLITE881South]

I know a young guy that when he's tightening the scope ring screws down, his hands are shaking so bad from the amount of torque he puts on them, if he slipped he would do some serious damage to his scope, or rifle. His dad about has a fit, but, hay, its the kids rifle. I saw him doing it, and had to turn my head I use a torque driver and, its been recently calibrated. I'll say this, when it ''pops'' it kind of makes me wonder about whats going on inside the scope. But, i guess it wouldn't be any worse than shooting a .223.

 

[Sully2]

The question has been asked on several occasions
what the torque for bedding screws and scope bases
should be so I though this might be helpfull.

"NOTE" These are based on full engagement of threads.

Wood, Fiberglass or Synthetic stock without bedding pillars-
40 inch-lbs.

Wood, Fiberglass or Synthetic stock with bedding pillars -
up to 65 inch-lbs.

Hard-use service-type rifles in synthetic with pillars-
up to 65 inch-lbs.

Law enforcement & military rifles are 65 inch-lbs on each
of the guard screws.

On rifles with three guard screws the middle screw should
be only slightly tightened.

Scope base screws 30 inch-lbs "MAX"

Windage screws 30-40 inch-lbs "MAX"

Scope ring screws (Aluminum Rings) 10-15 inch-lbs "MAX"

Scope ring screws (Steel Rings) 15-20 inch-lbs "MAX"

Note' If scope base and ring Screws have less than 5 threads
of engagement they should be replaced with longer ones.

Barrel to receiver Torque 35 ft/lbs minimum to 95 ft/lbs Max.

If an anti seize compound is used instead of a light oil use 65
ft/lbs max to prevent over torquing.

Per J. E. Customs

 

[Clark]

Barrel to receiver Torque 35 ft/lbs minimum to 95 ft/lbs Max.

If an anti seize compound is used instead of a light oil use 65
ft/lbs max to prevent over torquing.

Per J. E. Customs

I have experimented with 10 foot pounds and 1000 foot pounds to put them on and they shoot the same accuracy.

I have kinda standardized on 50-100 foot pounds to put barrels on.

It took 540 foot pounds to get this rusty 1939 Mosin Nagant barrel off, I cleaned it up, lubed it, and it took 200 foot pounds to get it back to the marks. I have since converted it to 300 Win Mag with a Krieger stainless barrel, and I put it on with 50 to 100 foot pounds to get it to line up with the marks for the extractor relief cut I made.

 

[Bob the nailer]

Great thread on torque specs. This will come in handy.

 

[CB11WYO]

subscribing

 

[J E Custom]

I have experimented with 10 foot pounds and 1000 foot pounds to put them on and they shoot the same accuracy.

I have kinda standardized on 50-100 foot pounds to put barrels on.

It took 540 foot pounds to get this rusty 1939 Mosin Nagant barrel off, I cleaned it up, lubed it, and it took 200 foot pounds to get it back to the marks. I have since converted it to 300 Win Mag with a Krieger stainless barrel, and I put it on with 50 to 100 foot pounds to get it to line up with the marks for the extractor relief cut I made.

Measure the torque needed to unscrew a 91/30 barrel after 73 years - YouTube

I have a little trick to remove old/difficult receivers that can save your receiver from over stressing and twisting that might help.

I use a standard Brownells receiver wrench and a large rubber mallet that applies plenty of impact shock and doesn't mark my wrench.

One or two good strikes and the receiver comes loose. I have only had one receiver that would not come loose and I had to cut a relief at the barrel tenon shoulder and the front of the receiver.

I am not sure how much torque it would take to damage a receiver and don't want to find out so the impact method works good and I don't run the risk of screwing up a receiver with to much torque.

Like you I like 50 to 100 lbs for the barrel to receiver connection (50 to 75 ft/lbs If any lubricant is used on the threads, and 75 to 100 ft/lbs if they are put on dry.

There is also less chance of rotating a good barrel in the barrel vice damaging the finish with the impact method using the rubber hammer.

Just another way to skin this cat.

J E CUSTOM

 

[Hired Gun]

To subscribe every forum thread has a little drop down box with the option to subscribe. Otherwise it needlessly bumps the thread and then I feel obligated to comment. So here is my $500 worth on the subject. It might save you an action someday.

The tightest factory guns we regularly see are Weatherby Vanguards. I put them in our 4 bolt aluminum lined steel vise and torque it down to 100 ft pounds on all four 1/2-20 bolts. I clock it so the action wrench handle is at 9:00. Then it takes 7-10 big blows with a 8 pound full sized sledge hammer to break them loose. I would wear out every rubber hammer made trying to do that on a Vanguard.

I have a 5 pound plastic dead blow and it will not budge a Vanguard barrel but the sharp impact of steel on steel shocks them right apart. A Remington will come off with 2 or 3 bumps or a whack with a 3 pound hammer or a few more with the 5 pound dead blow. The sharp impacts also work way better than hanging on a 4 foot cheater bar. The bar will try to bend things that the impacts work by vibration. Too light of a hammer and all you do it put hammer marks in your action wrench.

6 years now and never so much as marred the bluing or scuffed any Cerakote.

Putting barrels on. The 9/16" lug nuts on my truck call for 140 ft pounds. 1/2-20 take 100 pounds. Most barrels are 1"+. We go on at 100 ft pounds with Neverseize. That is nothing for a 1" tennon.

Browning A-Bolts with their paper thin action and 32 threads per inch might as well be welded on. I hate those things. I'm just waiting for the day I damage the engraving or have one gaul up. All it takes is for someone to damage the barrel threads with a scope base screw that is too long.

One other note on heavy steel hammers. On pistol sights I have found the heavier 3 pound hammer will drift really stuck sights without damage where the lighter hammer just dings them up. It's a momentum thing. Watch out for Springfield XDs and Kimber 1911's. They are stupid tight.

 

[J E Custom]

Just another comment.

I believe that a rifle, or any other firearm deserves a little finesse and there is always a way to work/fix it without beating it up, so I recommend/use methods that do not risk damaging any part whether it is a good or bad part.

This is one area that I don't use the "Get a bigger hammer" philosophy and so far I have been successful at all disassembly issues.

The rubber mallet has survived many years of use and is still does its job without damaging my wrench or the action so I will continue to use the method that works for me. and if it doesn't work
I resort to other methods to relieve the pressure/reason that I cant separate two parts.

PS: The only action/barrel that This method has not worked on had been assembled with Loctite
and a relief cut was necessary.

The main rule to follow is never over tighten/torque any part or screw. Use the proper torque for "ALL" parts and the proper tools and you will stay out of trouble.

Just My opinion.

J E CUSTOM

 

[Edd]

All rubber hammers aren't created equal.

Hammers : Rubber Mallet, 2 lb.

 

[Hired Gun]

The use of hammers of varying weight and materials has and always will be an accepted part of gunsmithing. Experience and training will help you choose the right tool for the job. Don't guess. If I am unsure we have access to the most experienced and respected smiths in existence. They are not regulars on any forums.

In the case of barrels sometimes the right frequency of vibration will move a joint that just simply twisting harder with a long handle will deform or break. If you don't understand it doesn't mean the principle is incorrect. Some need to see it work before they will try it. Vanguards will tune you up in a hurry.

Your report card is the firearm itself. If you leave marks, gouge or break something you failed. Be prepared to make it right no matter the cost. If your unwilling then pass on the job. Like a doctor I am obligated to do no harm and use only proven therapies for my patients.

I have yet to find the need to cut up a gun to save it. Cutting a relief groove no matter how neat is fatal damage to the take off barrel. Knowledge is power. Red Loctite releases it's grip at 482 degrees. Done improperly the heat is not without risk. There are methods to get the heat where you want it without cooking everything. Cutting a relief doesn't change that. If cutting it helped it loosen it was just tight to begin with.

I love guns and it pains me to see things ruined as I frequently do. Customers are trusting us to do the right thing. My tolerance for gun butchery is not what it used to be. This is why I just can't hardly participate in these forums anymore. Rather than be misunderstood or hurting someone's ego it's better to not say anything at all.

 

[J E Custom]

I love guns and it pains me to see things ruined as I frequently do. Customers are trusting us to do the right thing. My tolerance for gun butchery is not what it used to be. This is why I just can't hardly participate in these forums anymore. Rather than be misunderstood or hurting someone's ego it's better to not say anything at all.[/QUOTE]

+1

Ego should not be in the equation. The goal should be to help people that could use some guidance
and help keep then from making a fatal error.

Different opinions are necessary in order to give as many methods/information as possible and the reader has to decide which is best for him.

It is rare to find anything that has only one way for it to be done, differences in opinions are common and is the purpose of this web site in my opinion. also the customer should have trust that his Smith will do what is best for his project/build.

There is a tremendous amount of information available as long as we keep an open mind and leave our ego's and feelings somewhere else.

Not preaching, just commenting.

J E CUSTOM

 

[J E Custom]

Thanks JE,

I was just thinking about this today, and got my answer. I was wondering though, what about standard glass bed without the pillars? Is that any different from the torque specifications with the pillar bed?

Action screw torque is based on the stock material, not the action screw its self.
Pillars prevent stock material compression, So a stock with pillars can take more torque without compressing the stock material over time causing action screws to loosen or reduce the torque and possibly changing the group size or the point of impact.

Scope base and ring screws are much smaller and the torque values are based on the screw strength to prevent breakage.

It is common for stocks made of any material to compress over time and lower torque or loosen action screws so I always recommend pillar bedding all stocks that don't have them.

J E CUSTOM

 

[newmexkid]

Old thread but, always pertinent. Also, my old torque wrench gave up the ghost and I got the following from Amazon and it is sweet!
TEKTON TRQ21101 1/4-Inch Drive Dual-Direction Click Torque Wrench (10-150 in.-lb./1.1-16.9 Nm)
by TEKTON