Disaster.....Barrel Galls in New Bat Action

The probable problem is people fit their threads too tight.
I've done it twice. Since I went to a slightly looser fit no problems with just cutting oil on them.
If it feels like a close fit it's too close. Take another couple of thou off.

+2

Another problem is some old machines that have done a lot of threading up by the headstock have lead screws that are worn, and can be a tad out of pitch. That's why some will find the action will start loose and tighten up as it is scewed on. Truth is, when final fit, only a couple of threads are making contact.
 
Forget the anti-seize - use EP grease only.

This issue has come up in these forums many times over the years. In my experience, the only suitable lubricant to use on barrel threads and bolt lugs are EP-2 rated greases…and even those seem to vary from brand to brand. Keep the anti seize for assembling things with hardened fasteners, not soft 416 SS barrels threaded into custom actions.

I did my own tribological testing by doing a mockup of the ASTM 4-ball weld test like the lubricant manufacturers use by taking the materials the actions and bolts are made of, and rolling them together under pressure. I put the blank in a lathe chuck and faced it off to a finish similar to what one would find on a custom action, and put a piece of 4140 HT similarly finished on the carriage and “mashed” the two parts together while rotating the faced part at 35 RPM, and using a lever on the hand wheel with a weight suspended from it for torque control.

Every metallic based anti seize I tested failed almost instantly, with the exception of the pure lead based (hard to find these days), which lasted about five seconds. The only greases I tested under the circumstances that held up for a reasonable period of time were Pro-Long EP and Mobil-1 Universal Synthetic grease. The latter was the winner by far. If I recall correctly, I was able to mash the two parts together under slow rotation with approximately 10 lbs. of torque for twenty seconds before the pieces galled together.
 
+2

Another problem is some old machines that have done a lot of threading up by the headstock have lead screws that are worn, and can be a tad out of pitch. That's why some will find the action will start loose and tighten up as it is scewed on. Truth is, when final fit, only a couple of threads are making contact.



The old rule was that the odds of having more than about three threads actually in contact is still pretty true.

We used to see it on prevailing torque fasteners.

You put them on, tighten to stretch the fastener.

They are one shot things.

If removed they must be replaced with new.

They are as common as dirt on aircraft.

In many cases you could remove on and see that only a few threads showed deformation under rated load.

There might be an inch of threads that are together, but only a very few are bearing the load.
 
Just a question, if you all are cutting the tenon down to 1.055, are you also cutting the seating surface for the recoil lug to the same diameter, or are you fitting that dimension tighter?
It seems that a loose recoil lug could lead to inconsistent bedding.

I don't see why. The only place the recoil lug should bear in the stock is at the rear of the lug. The sides, front and bottom of the lug shouldn't be touching the stock.
 
Just a question, if you all are cutting the tenon down to 1.055, are you also cutting the seating surface for the recoil lug to the same diameter, or are you fitting that dimension tighter?
It seems that a loose recoil lug could lead to inconsistent bedding.


I'm sorry rain164845, I didn't understand the question....

I ALWAYS leave the tenon fit inside the recoil lug as tight as I dare. And I never set the lug on threads. And I use lugs up to 1/2" thick. And I only relieve the bottom. (I do relieve sharp corners on the metal lug itself to keep from shaving the bedding on reassembly)

And for me it isn't about bedding per se.....I believe that recoil lugs moving under recoil or promoting weird flexures in the system is a big problem. Especially with high recoilers.


opinionby




al
 
IME stainless on non-stainless (at least SS on Chrome Moly) is not prone to galling nor to the "stickiness" inherent to SS/SS

A certain action maker sold that concept, CM receiver, SS bbl and bolt, successfully for many yrs. I'm a believer.


It is the surface chromium on stainless that makes it gall.

Stainless (and especially pickled stainless) has very little exposed iron on the surface.
Those atoms have been removed from the metal.
The surface is mainly the chromium that was added to make 'stainless.'

It is very hard though not in a measurable way like using a Rockwell tool since it is really only about 1 atom thick.
 
You can buy it in a stick too, carry it in my range box.

I've only used it in a brush top can. I really like the stuff. It does all we need in our application, and then some. I really appreciate the lack of mess with it. IMO, the metallic products are best in extremely high heat and corrosive environments. I'm not sure how some things that are not well suited for our use become accepted as the end all, be all. I think it boils down to, if it's good enough for "so and so", it must be the best. Yes, they'll generally get the job done but we aren't exactly testing their abilities in our applications, IMO. FWIW, some of the copper products are said to not be suitable on stainless.

As has been mentioned already, a good grease is better for barrel tenons than a metallic anti seize product, IMO. I like the white anti seize and it is not metallic. If I didn't like it as much as I do, I'd use a good EP moly based grease.

For trial fitting of parts by hand, I still think a good cutting/tapping fluid is best but, as usual, YMMV.
 
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I've been using ARP Ultra-Torque assembly lube for probably ten or more years now. I can't say it works any better or worse than other options but it has worked for me.
 
I've been using ARP Ultra-Torque assembly lube for probably ten or more years now. I can't say it works any better or worse than other options but it has worked for me.

Hey, that's a great idea! I know that I've use assy lube in places where oils and greases weren't getting it done due to small surface/high pressure. I disremember the several brands but remember that you could dip a stick in it and it'd lift out of the can like taffy....
 
I will mention a couple of things that relate to this thread but only to what it has evolved into. My early Viper's insert was thread milled, which gives it a different surface finish in the threads. It seems to me that a that two very smooth finishes have the greatest tendency to gall. I have used the grey Permatex, the common VersaChem, and on occasion (but not for the first application) Pro Shot Gold with no problems. The Viper's action threads are purposely slightly tapered to better distribute the load. They get slightly tighter to the back. I think that this is a good thing, and it is probably easier to make that way with a thread milled insert. Finally, with V type threads I see no reason for a close fit, as long as it is reasonable and safe. I am finally to the point where I will be ordering a lathe in the next three months and my intention is to make test tenons for the practice, but also to try in any action that I rebarrel. I will want to make these from a material that cannot gall in a stainless action. What material would you suggest?
 
material

I will mention a couple of things that relate to this thread but only to what it has evolved into. My early Viper's insert was thread milled, which gives it a different surface finish in the threads. It seems to me that a that two very smooth finishes have the greatest tendency to gall. I have used the grey Permatex, the common VersaChem, and on occasion (but not for the first application) Pro Shot Gold with no problems. The Viper's action threads are purposely slightly tapered to better distribute the load. They get slightly tighter to the back. I think that this is a good thing, and it is probably easier to make that way with a thread milled insert. Finally, with V type threads I see no reason for a close fit, as long as it is reasonable and safe. I am finally to the point where I will be ordering a lathe in the next three months and my intention is to make test tenons for the practice, but also to try in any action that I rebarrel. I will want to make these from a material that cannot gall in a stainless action. What material would you suggest?


I use a lot of 1215 and have for the past 15-18 years, all of my tendon stubs and core seating punches ..........wonderful stuff to machine. Caliber sleeves for Hoover Tipping Die, die punch holders, caliber sleeves and seating stems for Vickerman seating dies, extended shell holders etc....but always use some sort of lube for stainless, I learned the hard way!

SB heavy 10 for machine with high speed steel tooling and some carbide depending...........

Rick
 
I will mention a couple of things that relate to this thread but only to what it has evolved into. My early Viper's insert was thread milled, which gives it a different surface finish in the threads. It seems to me that a that two very smooth finishes have the greatest tendency to gall. I have used the grey Permatex, the common VersaChem, and on occasion (but not for the first application) Pro Shot Gold with no problems. The Viper's action threads are purposely slightly tapered to better distribute the load. They get slightly tighter to the back. I think that this is a good thing, and it is probably easier to make that way with a thread milled insert. Finally, with V type threads I see no reason for a close fit, as long as it is reasonable and safe. I am finally to the point where I will be ordering a lathe in the next three months and my intention is to make test tenons for the practice, but also to try in any action that I rebarrel. I will want to make these from a material that cannot gall in a stainless action. What material would you suggest?

Boyd,

I've always used aluminum to make tenon gages...easy to machine, and I have plenty of it lying around. Plus, not knowing your experience with lathes and threading, it's forgiving to work with. You can make mistakes and get away with it most of the time, so you're not crashing your machine, breaking tools, etc. Great stuff to learn to thread on. I've never used it in a stainless action, though.

If I was going to make one in steel, I'd probably use 12L14 or 1144. Both are easy to machine and give nice finishes...especially 12L14. Jackie is a big fan of 1144...his talking about it turned me on to it. I'll leave it to the metallurgist-types on the forum to cite any compatibility issues these steels may have with stainless.

What kind of lathe are you gonna order?

Justin
 
It's not hard to

Question/comment from someone not being a machinist or a gunsmith, but would it make sense to re-cut the threads of BAT actions to the size that they were expected to be?

thread for bat actions. When you have done enough of whoever's actions you have a pretty good idea of what the tenon threads are going to end up at. And besides, alot of rifles come into the shop already glued in.
If in doubt I'll err on the side of a little smaller thread everytime. It will shoot just as good. Tight threads aren't a "badge on honour" as some make it out to be.
On thing that can stick a bbl into a action is if you don't put a lead in cut on the thread relief and also the butt of the tenon. If you don't you will leave a tiny sliver a thread that can break off and make for a really bad day.

Richard
 
Question/comment from someone not being a machinist or a gunsmith, but would it make sense to re-cut the threads of BAT actions to the size that they were expected to be?

Unless there was something amiss with Bats threads I'd leave it alone. Recutting them for no reason other than putting the tolerance into the action is a bit backwards. All manufactures have their thread requirements available and should be what is followed when threading a barrel. You surely would not use a xyz action for a thread gauge, for any other action. The better practice is to use thread gauges and verify whether your action is tight or loose. The confusion lies in what exactly does loose mean. With "Fine" threads there is not much between loose, looser, and sloppy.

I for one would like to see a standard so barrels could be interchanged but that's probably never going to happen.With ANY manufactured product, when you machine threads to fit, it, you cut them either to a lower tolerance or cut to fit each and every item.
 
thread for bat actions. When you have done enough of whoever's actions you have a pretty good idea of what the tenon threads are going to end up at. And besides, alot of rifles come into the shop already glued in.
If in doubt I'll err on the side of a little smaller thread everytime. It will shoot just as good. Tight threads aren't a "badge on honour" as some make it out to be.
On thing that can stick a bbl into a action is if you don't put a lead in cut on the thread relief and also the butt of the tenon. If you don't you will leave a tiny sliver a thread that can break off and make for a really bad day.

Richard

Bingo.....
 
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