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I've noticed everyone I've had chamber a barrel for me does things a bit different. They indicated in different places, some use solid reamer holders some floating, and some bore out part of the chamber before using the reamer. What methods do you prefer and why?

Who does a good chamber job at a reasonable price with decent turn around time? More importantly who stands behind their work. It's pretty frustrating when things don't work and the smith blames the barrel and the barrel manufacturer blames the smith.

I've got several barrels on hand and need to start getting a few chambered.

Thanks,
Bb

For me depends on the chamber.

Indicating is the same barrel chucked in lathe muzzle supported with a center in the head stock, Still need to build my adjustable indicating bar center. It's design was posted here by another user years ago and is a very good design.

Indicating rod in the bore, indicate the length of the chamber to within .0005" or better for precision rifles. and have at it.. the chamber needs to be as close to center (concentricity) and as straight( angularity) as possible in relation to the bore where it is located in the barrel. I think a lot of guy over think the process and don't really understand what is going on. once that bullet is in the bore the chamber is out of the equation

If the chamber is fairly large yeah bore out the bulk first, no sense in beating up your reamer doing roughing work.

Form reaming can be difficult and soem forget to slow the machine down slower then conventional reaming speeds for the material you are working with, You can't go to slow, lots of high sulphur oil and clear the chips often. develop a feel on the tail stock to know how your reamer is cutting and if it's having a hard time. Finish the chamber's last .010" or so by hand and leave .0005"-.001" for polish. You've got .004" to .006" headspace to play with.

But are we talking a Bench rest rifle, a precision rifle, (tactical) a hunting rifle, or a big game gun? different tolerances and attention to detail for each of these,

I'm sure if it could be done someone would want their bench gun with an internally ground chamber.

James Parfet wrote about boring a "near perfect" chamber. Wrote it took him about 45 minutes once he got used to it ("Gunsmithing Tips & Projects," Wolfe Publishing, 1989. All kinds of good stuff in it.) Anybody here try it?

I chuck the chamber end of the blank in my 4 jaw with the muzzle through the spindle and indicate it in with a spider or use a mandrel on a center in the muzzle. Indicate the bore to .0005, face the blank off, turn and thread the tenon, and cut the chamber using a JGS floating reamer holder. The big lathe I prefer to use for barrel work has flow through coolant system that pumps through the mandrel in the bore. I use a Rustlick brand coolant, don't remember the model but it's the orange one.
I prefer to use a finish reamer from the start and once I start the job I want to concentrate on only it until I'm done. Just more comfortable that way.

I've used lathe dogs and even a Crescent wrench to hold the reamer in the past as well as a floating reamer holder I had to build as a project in gunsmith school. I've been using the JGS unit for 8 years now and like it the best of all that I've tried. I've also done a chamber or three using a steady rest and prefer the 4 jaw. Many ways to skin the cat, just have to use what works for you.

I do basically the same thing after the barrel is set up in the 4-jaw, but add a step: after the face on the blank is done, I make a small cut with a boring bar on the bore, then recheck setup using a centering bar. Amazing how the bores can be off a thou or four from the OD. Once the bore is centered to within .0005, then and only then do I start to thread the tenon..

I want that bore centered...

I use a cathead on both ends in the headstock. I don't use and wouldn't use a 4 jaw unless you have a soft material between the jaws and the barrel. The jaws can bend the barrel.



My chuck side cat head built from scrap. I like copper tips as it is softer than brass. I have a set of Deltronic Pins for ea. bore size that I chamber. They are a set of 25 in .0001 increments. I indicate both ends initially. I cut the tenon and thread first. I predrill the chamber to get rid of material and to allow either of my long reach indicators to reach as close to the throat as I can. I want my chamber to be coaxial to the throat. I taper bore to the throat. It is time to chamber now. I do not like floating reamer holders. I push and don't allow the tailstock or other things to influence the direction of the reamer.
Just my way and what I've learned that works best for me. I no longer do this for the public. I'm finishing up on my 280AI barrel as we speak.

I only build for myself , i prefer to chamber from the head stock and center the bore as close as possible from the outside diameter of the shank and then use a indicator rod to dial center within .0005 . I use a cat-head to make sure the barrel is indicated from both ends. I then cut the tenon and face off to length , cut the bolt head recess since i only use 700 actions and then thread the tenon , i then cut my chamber with a finishing reamer only at 115 rpm and use a Bald Eagle Floating reamer holder for this. After chamber is cut i then polish the chamber . I then take the barrel out and polish up the complete outside with wet sand paper using the three jaw chuck then after barrel polish i cut the barrel to length and back in the 4 jaw indicate and cut the crown . I have chambered from the steady rest but not my favorite way of cutting chambers and only do this when the barrel is to short to chamber from the head stock. 6.5-06 setup in steady rest . I moved the steady rest closer to the chamber end before I starting cutting the chamber. Rifle after finished 6.5-06.

Butch pointed it out, And I guess I should have said it but it kinda goes without mentioning that anytime you have a finished part being chucked on in the lathe yes you need to use some padding on the jaws. I guess it's second nature with me just to do that no matter what. If not you will have some sanding and polishing to do afterwards. No way to do a professional job, and be sure the padding you use is thick enough as a little piece of .062" aluminum is not enough to prevent the jaws from digging in.

I use copper bushing i Wrap around the barrel shank. You can see the light reflect off it in the steady rest setup photo

I use brass pads between the jaws and the OD to keep them from marring or digging into the blank. And as Redneck suggested, yes it's the bore that's indicated not the OD. I could care less what the OD is doing as long as I'm centered on the bore.

I would never chamber a barrel just indicated from the outside diameter of the shank

nor would I waste my time indicating the muzzle any closer then a couple of thou on the bore. It's not needed nor will it make a hill of bean difference.

go take a trashed barrel and slice it up in about ten pieces and see how far the bore drifts in the barrel granted on a good barrel it's not much usually within .010" of center to the OD but I've seen some real bad ones .050" off center.

So indicating the muzzle should only be done to insure that the barrel will mount on the receiver in concentricity as close to the axis of the bolt as possible. this will prevent gross corrections in windage and elevation in sights. Remember .0005" run out on the shoulder = .007" at the muzzle with a 20" barrel. Give or take I'm using Remington Dimensions too.

So if your muzzle is dialed into within .002" run out over 20" you're better then .0001" per inch of run out?? does it really need to be that damn close?? nope because the bullet was just traveling god knows how far off center of bore axis just 10" prior to the muzzle. most people can't see .005" run out in a lathe spinning. so again indicate the bore at the muzzle for squareness of the shoulder to the receiver ring and to reduce bore sighting issues. out side of that there is not reason but to waste time indicating a muzzle to .0005"

I always indicate off the bore. Depends on barrel size I only have a 1 1/8 spindle bore. I either use a face plate with center and a turning dog and steady rest for large barrels. Or a 4 jaw chuck for conventional contours. I have made some 1 1/8 bushings about 2 1/2 inches long tapered on the inside for the different contours that I use to center muzzle end of the barrel in the spindle bore. I use a Clymer floating reamer holder turn slow and use black sulfur and lard based thread cutting oil for both reaming and threading. Use a finish reamer from start to finish. I do the last .010 by hand with action screwed on. Many many ways to skin the cat.

Yep!
How do you indicate the bore in the steady rest?

Kind of what I was thinking If I was looking for a re barrel and saw that set up I may look a bit more. But to tell the truth have never tried it maybe the threw hole is small and this is a solution?

Steady rest is fine if you first turn your tenon to be exactly coaxial to the bore or you will be chambering a bore that is running out in the steady.

I have a question for you really experienced guys, I am using an outboard spider and a cathead mounted on a back plate to dial in my barrels. I am using a long reach indicator at two points inside the bore of the muzzle and can dial it into ~.0005" at two points in the bore.

When i look at the chamber end in the outboard spider it looks like it is WWWWWWAAAAAAAAAAYYYYYY out spinning ecentric? is this normal? or is this just becuase the bore is not striat in the barrel?

Should i be dialing in both sides of the barrel to .0005" on the muzzle end and chamber end, to get the whole bore running true through the spindle?

You are doing it the best way. All barrels are curved to some extent. Ignore the other end. When on the chamber end you want to notate the high spot so you can clock it at 12:00 on the action. I dial the throat and then 2" farther in. Then thread, bore and chamber with the 2" portion dialed into perfection. This get's the bullet a straight into the bore as humanly possible. Do the same on the crown and muzzle threads to get the bullet out of the bore as straight as possible.

When you have your barrel dialed in how much TIR are you seeing on the other end (out board spider)? Im only asking becuase the last barrel i dialed in seemed like alot

And where did you get this info? Off the internet probably. You couldn't make a bore banana shaped if you tried. They may not be perfectly straight, but they ain't banana shaped.
Give me a list of the winning competition gunsmiths using the Gordy method.
Now tell me what indicator you use that is long enough to reach in to the throat and an additional 2".