Importance of truing threads?

[Dusty Stevens]

I know when you have a nice trued action, nice threads on both barrel and action, and a perfect shoulder when you snap it together by hand you have to have a wrench to get it back loose. I have no idea how he had movement if everything was in good shape

 

[TRA]

The first indication of movement is to look at the action face and the barrel shoulder. If they appear to stay fresh machined, then they are not moving. If they are moving the surfaces will take on a dull color. If two metal surfaces are moving enough they will appear as if valve grinding compound was used for assembly lube. Another is if they develop deformation.

With only ~.060 shoulder and a large enough barrel, I don't see how it cannot move. With threaded joints, vibrations, harmonics, and extreme pressures, something's got to give. Does it matter? With today's technology, it does not appear to. There's got to be a better way to plug the breach end of a rifle.

 

[Alex Wheeler]

When I am talking loose threads, I am not talking hardware nut loose. They are still well fitted threads. But they are about .001"-.002" smaller than they "could" be.

 

[Alex Wheeler]

The first indication of movement is to look at the action face and the barrel shoulder. If they appear to stay fresh machined, then they are not moving. If they are moving the surfaces will take on a dull color. If two metal surfaces are moving enough they will appear as if valve grinding compound was used for assembly lube. Another is if they develop deformation.

With only ~.060 shoulder and a large enough barrel, I don't see how it cannot move. With threaded joints, vibrations, harmonics, and extreme pressures, something's got to give. Does it matter? With today's technology, it does not appear to. There's got to be a better way to plug the breach end of a rifle.

A lot of f-class and LR BR HG rilfes are built on Bat M actions with 1.250 30" straight barrels. That leaves a .062" shoulder or less. Barrel movement at the joint would be a serious problem that I do not think we would miss. We used to look for "fretting" under main caps on out drag engines. I dont think there is enough load or harmonics involved in a barrel joint that you would see evidence of fretting even if there was movement.

 

[butchlambert]

Well,
I guess I've larned sumpin on the innernet, so I better tig weld mine to eliminate the movement.

 

[eddief]

Just a couple of tacks should do it Butch.

 

[butchlambert]

Just a couple of tacks should do it Butch.

Yup, just what I thought.

 

[Dusty Stevens]

Yup, just what I thought.

Use red loctite as well as punching the threads to lock r in real good. As eddie would say “this is better’n the funny papers.” I know benchrest guys that only keep their barrels hand tight so they can change em easier and they actually win matches.

 

[johnfred1965]

If you guys missed targets, the way you miss the point of this thread, you would never get into the Hall of Fame. Of course, shooting a finely machined Bat benchrest action, with a barrel threaded by a professional with threads smooth as a baby's bottom and consistent down to a few tenths, is going to shoulder up, stay tight and shoot great. My apologies to MRAM, but a rifle put together with the threads he was cutting a few weeks ago, would not shoot optimally. And the famous championship barrel tenon that has been paraded through these pages was probably jammed up in the action so tight it wouldn't move and it shot great too. How many gunsmiths have won a championship with the first barrel they ever threaded? Not after you hung out a shingle, but the first one you chucked up in a lathe?

 

[butchlambert]

If you guys missed targets, the way you miss the point of this thread, you would never get into the Hall of Fame. Of course, shooting a finely machined Bat benchrest action, with a barrel threaded by a professional with threads smooth as a baby's bottom and consistent down to a few tenths, is going to shoulder up, stay tight and shoot great. My apologies to MRAM, but a rifle put together with the threads he was cutting a few weeks ago, would not shoot optimally. And the famous championship barrel tenon that has been paraded through these pages was probably jammed up in the action so tight it wouldn't move and it shot great too. How many gunsmiths have won a championship with the first barrel they ever threaded? Not after you hung out a shingle, but the first one you chucked up in a lathe?

Tony Boyer never chambered a barrel. I've had better luck with a Panda. My threads are not snug. I think a few of us have chambered a barrel that has shot official zeros and won something. How many Hall of Fame BR shooters are on the forum? or other forums?

 

[Dusty Stevens]

Tony Boyer never chambered a barrel. I've had better luck with a Panda. My threads are not snug. I think a few of us have chambered a barrel that has shot official zeros and won something. How many Hall of Fame BR shooters are on the forum? or other forums?

Bart Sauter is here. Everybody else is out practicing.

 

[mram10]

John Fred,
No offense taken
I went from butchering barrel stubs to building 4 rifles in a month with my first lathe. Tolerance is right where I want it and we’ll see how they shoot very soon which is the real test. When I measured barrels from the factory and compared with what I can build now, there is no comparison. Funny thing, those factory guns shoot pretty darn good with crumby tolerances.

 

[STS]

Use red loctite as well as punching the threads to lock r in real good. As eddie would say “this is better’n the funny papers.” I know benchrest guys that only keep their barrels hand tight so they can change em easier and they actually win matches.

I don't shoot BR these days but when I did I saw a few shooters hand tighten them also. Some of those same guys would get a REAL FUNNY look on their face when they shot about 5 inches of vertical on one of their 100 yard targets from their barrel working loose. Saw it more than once. I'll help myself to about 75 or 80 foot pounds of torque if you don't mind.

 

[johnfred1965]

Tony Boyer never chambered a barrel. I've had better luck with a Panda. My threads are not snug. I think a few of us have chambered a barrel that has shot official zeros and won something. How many Hall of Fame BR shooters are on the forum? or other forums?

Tony may not have chambered a barrel, but I'm sure he didn't go to the local vocational school to have it done. How many barrels do you have to craft to get the ONE that shoots zeros? Read this again, because you still aren't getting it.

I am not claiming any expertise here. I could build rifle, it would be safe and I could hunt with it, but I don't have the talent to build a bench gun. Many, many garage gunsmiths can do the same, but I and many others would have to chamber barrels for years to gain the talent and experience and reputation for the best shooters to come to me for a barrel. I have to respect that talent in the builders and shooters on this forum, especially since I don't have that level of talent. I have noticed that some of these talented people, however, deserve less respect when an opinion is presented that is not their own.

 

[mram10]

I would be curious to see if you randomly took 20 of us, gave us all the same components to build a rifle and saw how they shot.

 

[carlsbad]

I would be curious to see if you randomly took 20 of us, gave us all the same components to build a rifle and saw how they shot.

Lets see how yours shoot before we start the grand experiment....what is your prediction for 100 yd group size?

--Jerry

 

[johnfred1965]

I would be curious to see if you randomly took 20 of us, gave us all the same components to build a rifle and saw how they shot.

Like I said, I'm sure I could build a hunting rifle, but my F-class rifle was built by John Pierce, and my LR tube gun by Gary Eliesio and Jim Borden!

 

[johnfred1965]

Lets see how yours shoot before we start the grand experiment....what is your prediction for 100 yd group size?

--Jerry

I've got faith in him, since everything he learned, he learned on here! He did build some heavy chamberings though, so I am not expecting one hole groups, simply due to recoil.

 

[Cloudrepair]

There have been many things concerning the threaded joint on a rifle discussed.
I know truing the threads on a reciever will make it all work better together. Everything in the right place will help, how much is the question and is it worth it for its purpose.
If the threads are concentric to the bore of the reciever and perpendicular to the face it will not come loose as easy it will center up the bore of the barrel better.

I have learned a lot from the people here and I am thankful for it.

There was a topic brought up that concerns some of the threads taking more load then others
I have a idea to help with that.
I'm sure some will see it as a fix looking for a problem.

The first barrel I threw in the lathe was a bartlein 7mm 9 twist, I threaded and chambered it for a savage in 7mm-08AI
Maybe not a good cartrige for Br record setting but it is very accurate so I pulled it off thinking I don't want to burn it up. Now I have a 6.5x47L on it that is very nice maybe better.
maybe a good excuse to get another action?
That barrel i believe could be competative.
Maybe that doesn't count because I have been runing lathes for many years before I ever decided I wanted to do this kind of thing

 

[mram10]

Jerry, Not sure what they will shoot at 100. I never shoot at 100. I zero at 300 and mainly shoot at 300 and 500 for load testing.
Johnfred, I’ve learned a lot on here, but far from everything I know. I had a friend I watched for years.