Buch chuck or 4 jaw when using a steady rest?

[bored184]

When forced to turn a barrel between centers is it best to use a 3 jaw adjustable buck chuck or a standard 4 jaw. I've watched the grizzly DVD with Gordy Gritter but my head stock is to long to use that method. I'm currently reading through The Complete Illustrated Guide To Precision Rifle Barrel Fitting. It's a great book but I'm still coming up with more questions then answeres.

 

[Terry]

As a test I chambered one of my barrels using the between centers method. My 3 jaw Chuck worked fine. Max run-out .001.

 

[bored184]

I could also use a collet chuck. I'd have to go looking for all the collets buts it's also an option.

 

[butchlambert]

You will have to put muzzle and breech between centers to make a truing cut on both ends before putting it in the steady. For a top quality job-a 4jaw.

 

[Dusty Stevens]

I cant see that there would be a difference between an adjust-tru 3 jaw and a 4jaw. Both do the exact same thing in this instance

 

[butchlambert]

I cant see that there would be a difference between an adjust-tru 3 jaw and a 4jaw. Both do the exact same thing in this instance

Didn't see the TruAdjust. Still matters not if a truing cut on each end is not made.

 

[DaveTooley]

When forced to turn a barrel between centers is it best to use a 3 jaw adjustable buck chuck or a standard 4 jaw. I've watched the grizzly DVD with Gordy Gritter but my head stock is to long to use that method. I'm currently reading through The Complete Illustrated Guide To Precision Rifle Barrel Fitting. It's a great book but I'm still coming up with more questions then answeres.

I'm confused. You want to turn the barrel between centers but ask about what chuck to use. By definition between centers doesn't involve a chuck.
Although I have used a chuck to drive the lathe dog.

 

[bored184]

I'm confused. You want to turn the barrel between centers but ask about what chuck to use. By definition between centers doesn't involve a chuck.
Although I have used a chuck to drive the lathe dog.

Correct and I apologize for my ignorance. Still trying to learn the the correct terminology. What would this method be called if one is forced to use the chuck, steady rest and tail stock?


There's a diagram in the book the book that to me makes nonsense. I get that I would need to turn betweens centers to make a trying cut but the diagram doesnt show it. It shows the breech end in a chuck and making a truing cut on the muzzle end. I dont know if I can share the diagram on here because of copyright issues.

 

[butchlambert]

I'm confused. You want to turn the barrel between centers but ask about what chuck to use. By definition between centers doesn't involve a chuck.
Although I have used a chuck to drive the lathe dog.

Yes sir, turn a center in the chuck and drive with the lathe dog. You can turn an thread the tenon, but will still have to put it in the steady to chamber it.

 

[butchlambert]

Correct and I apologize for my ignorance. Still trying to learn the the correct terminology. What would this method be called if one is forced to use the chuck, steady rest and tail stock?

I would call it chambering in the steady.

 

[Spotshooter]

One other option you have would be to use something like the Viper Action Jig to dial in the barrel and thread and chamber using that.... It wouldn’t be as strong as putting the material directly ahead of the chuck, but people do it.

I have both Gretan’s and Bob’s (Viper action jig) but haven’t tried them for threading or chambering yet...
IIRC there was a thread on that over on AR15.com and Bob weighted in about doing it...

Found the link - https://forum.snipershide.com/threa...g-ptg-action-jig-for-tenon-chambering.197072/

 

[GenePoole]

Wow. Blast from my past.

I've since built a Viper-like fixture that doesn't suffer from all those problems mentioned in the thread. It threads directly to the spindle nose and eliminates 5 or 6 inches of stick-out.

 

[tobnpr]

For the muzzle end truing cut, I don't think it matters much whether it's done with the breech in a chuck of any sort with acceptable runout or dogged in a center.

Whatever minimal runout exists at that end will not matter at the live center on the other end that's in the bore.

Once set up, I make the muzzle truing cut, and flip end for end it absolutely matters- Set-tru or collet needed to hold the trued muzzle end.

If the breech end has a straight cylinder or decent taper I will true several inches, and let the steady ride ahead of the actual tenon. If its a bull or similar contour, the steady will need to ride on the tenon- and then it becomes a choice of whether to cut the threads before or after the chamber is cut. With soft brass steady fingers/tips, they can wear pretty quickly on threads and introduce unacceptable runout so it may be preferable to chamber first- then stick a precision live center in the breech and cut the threads.

It's critical to have a high-quality live center for this work- cheap Chinese shit with 3 or 4 thousandths tir won't cut it.

 

[DaveTooley]

I stand corrected. Butch is correct turning a sacrificial center works also. A 3 jaw works fine as you true up the center and then never remove it until the work is completed. I prefer to use a center in the headstock. Better rigidity if nothing else. Also I use a solid, non rotating center in the tailstock when threading. Again rigidity. Some anti seize and don't over tighten the tailstock. When I cut the chamber I run the steady rest on the threads. No matter what I did I've never been 100% happy with running the steady on the cylinder section of the barrel.

Of course all of this is predicated on having accurate centers in the barrel.

 

[DaveTooley]

Doing it with centers on both ends and using a lathe dog allows you to take it out of the lathe and easily check thread fit. All will go back to the same place. That is as long as you use the same spot to drive the lathe dog.

There are many paths that we can take to get to the same place. With time you'll get comfortable your methods.

 

[paperpuncher]

When forced to turn a barrel between centers is it best to use a 3 jaw adjustable buck chuck or a standard 4 jaw. I've watched the grizzly DVD with Gordy Gritter but my head stock is to long to use that method. I'm currently reading through The Complete Illustrated Guide To Precision Rifle Barrel Fitting. It's a great book but I'm still coming up with more questions then answeres.

"my head stock is to long to use that method" depending on how much too long you can save a few inches by eliminating the chuck and building a spider to replace the chuck. This will buy you maybe 3". My lathe is too long thru the HS with a chuck but I can make it work with a spider. Just a little food for thought. Also if you really wanted to do it thru the HS you can simply make an extension to screw onto the barrel that will make it long enough to adjust from the left side. Nothing wrong with the steady and centers just throwing it out there

 

[butchlambert]

My Clausing is long in the headstock and as paperpuncher says, I removed the chuck and now I have catheads on ea. end of the headstock. I think Jackie Schmidt mentioned on the other forum that his little lathe was too long in the headstock and he reamed the bore through the spindle and made a fixture that holds ID and OD ground bushings. He trued the muzzle between centers and then slid the muzzle in one of his precision buttons in the headstock and the other end in a 4 jaw.
As Dave said, a lot of ways to skin the buzzard.

 

[DaveTooley]

I can do 25-24" barrels in my Haas TL-1. For shorter barrels I have bushings, aluminum and acetal. I put O-rings on the OD for a very tight fit. The ID's are diameter specific or have O-rings that snug up on various diameters.

 

[tobnpr]

No matter what I did I've never been 100% happy with running the steady on the cylinder section of the barrel.

What issues/concerns have you had with this, Dave?
When I use the steady on either the cylinder or the tenon, I always set up two indicators (top/side) before pulling the tailstock center to check for movement. I've never noticed any faults in that setup vs on the tenon.

 

[DaveTooley]

Bore alignment, concentricity issues. My guess is the closer the steady is to an accurate trued center the better off you are. Even if the barrel is not perfectly aligned with the tailstock the bore should be concentric with the OD. It's been a long time since I've had to do a barrel between centers bit I use a pusher on the reamer so a very slight bit of misalignment doesn't cause a problem. Concentricity does though.