Chamber reaming question

Do you hold the reamer in your Jacobs chuck in the tail stock?



yes. But I may have found a better way.


Holding it in the tail stock chuck may have been your problem... that isn't a good procedure in my mind..
 
Yeh

Sounds like he has a LOT of problems.
If he is holding that reamer in a Jacobs Chuck, I would bet his chamber is coming out about .002 to .003 too large.......jackie
 
Rmorr01: You're asking folks to rehash the entire process, it would seem. Suggest you do a site search here. Use "chamber reaming" in the keyword box. This will produce a virtual textbook on the subject and will probably answer all your questions and more. This has been the topic of several excellent discussions, and will reveal methods, equipment, and about everything else relating to the process, as practiced by some of the most talented and able folks anywhere. You might also benefit from purchasing Gordy Gritters' chambering video from Grizzly Industrial.
This will take some time and effort on your part, but the results will be worth it. Remember, there isn't any "15- minute short course" on the subject.
 
Anyone have any fixes/tools or solutions. Thanks. :)

Chambering is really not that hard, but you need to know how to run a lathe first, so learn to indicate a workpiece in, turn diameters, thread etc, then get into the nitty gritty of chambering. Start with a $79 heavy barrel from Midway and if you screw it up, who cares, face it off and try again.


Basic starting Tools

1-2" micrometer
6" dial calipers
Interapid test indicator with long stylus.
Basic Starrett dial indicator set
Mag base
Set of range rods.
Floating reamer holder.
General lathe tooling
2" Lathe dog
2" aluminum round stock for general use.
1" same
Finish reamer and go gauge

Books and videos
 
Anyone have any fixes/tools or solutions. Thanks. :)

I would suggest you start by the old method of using the barrel set up in a steady rest and the reamer pushed by the tail stock...

What training have you had?
 
Dennis makes a good point.

You would be surprised at the Gunsmiths who simply chuck the muzzle end up in a 3-jaw, run the OD of the barrel at the chamber end on a steady rest, and, using a floater, ream the chamber. Most chamber ends run reasonably close, as the blank is turned on a center that is true with the ID. Granted, the ID will not run very true up in there, but for many applications, it might not even matter. The floater takes care of any binding. In the end, the chamber will not run dead true, but sometimes all you need is good enough. It depends on the application.
For the vast majority of Rifles, this just might work as good as all of this anal stuff that we do to insure that every job is as perfect as our machinery will make it.
Many of us tout that chambering barrels isn't that big of a deal, but keep in mind, there are those of of us have 40+ years of machine shop experience under our belts. Heck, I can darned near do this sort of stuff blindfolded. But, Trust me, if you get careless, you can make a big mess in a hurry......jackie
 
You would be surprised at the Gunsmiths who simply chuck the muzzle end up in a 3-jaw, run the OD of the barrel at the chamber end on a steady rest, and, using a floater, ream the chamber.

There’s an add for one of the gunsmithing lathes that shows that very scenario. I wonder how many people have seen that and thought it was the correct way.
 
I would suggest you start by the old method of using the barrel set up in a steady rest and the reamer pushed by the tail stock...

What training have you had?

I learn as I go, I have a machinist friend as a mentor. I have chambered / threaded / shouldered / test fired this practice barrel a few times; but am still green @ this, I cut down the chambered end of the barrel / end face it then start over for practice( barrels getting really short now, but meh it was only $80 - order up another. My problem is finding a consistent method in chambering, some are better then others. I'll keep trying things till I get it. Turning is easy but this chambering is a real B#tch right now. Hopefully will work out the kinks this week. I do this as a fun hobby. Always have challenges in the beginning but thats part of learning and I'm enjoying it. Range rods and Floating reamer holder are on the list for things to get, Thanks guys. Have fun, B=safe.

Happy Shooting, Robert :)
 
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I'll keep trying things till I get it. Turning is easy but this chambering is a real B#tch right now. Hopefully will work out the kinks this week. I do this as a fun hobby. Always have challenges in the beginning but thats part of learning and I'm enjoying it.

Range rods and Floating reamer holder are on the list for things to get, Thanks guys. Have fun, B=safe.

Happy Shooting, Robert :)
Explain what steps in the chambering process you are having difficulty with. Reamer holding, spindle speed, type or amount of lubricant per reamer entry, how far to run the reamer in each step, cleaning the chamber for each reamer entry???

The use of range rods and a floating reamer holder CAN (not will, but can) cause you more trouble than you can imagine if you are trying to cut a benchrest precision chamber, especially if you are depending on the range rods for bore alignment and depending on the floating reamer holder to correct for misalignment of the bore.
 
Jerry,

Would you mind elaborating on your particular issues with the reamer holder? Range rod?

This has been working quite well for me, then, re-checking with the long stylus.

Ben
 
Jerry,

Would you mind elaborating on your particular issues with the reamer holder? Range rod?

This has been working quite well for me, then, re-checking with the long stylus.

Ben
Using the range rod for rough alignment is OK, especially for 3, 5 or 6 groove barrels. If you try to indicate on the range rod sticking outside the barrel for final alignment you are only extrapolating the curve in the bore and lining up on the extension of that curve. Do your final alignment with a good quality indicator that will reach into the chamber neck area. The chamber neck area is where the bullet gets presented to the bore.

On floating reamer holders, sometimes they float and sometimes they don't based on several factors including how much the lathe tailstock is out of alignment with the chamber and how well the holder truly "floats". Most floating holders only float in a direction perpendicular to the rotating axis of the lathe (spindle). A floating pusher is much better since it can float axially as well as radially. The error resulting in this would appear as the chamber body being 0.002"-0.005" or so oversize. This is not a problem in a hunting chamber, but not desirable in a benchrest chamber.

During this alignment process also line up the muzzle bore with the rotating axis. A way you can tell if this is not done properly, as you change barrels, the misaligned muzzle bore will cause the POI to be off from the previous zero by several inches to a few feet. When the action and stock axis is pointing one direction and the muzzle is pointing in another direction the gun will not recoil consistently in the bags. If you slide the scope off the bases or rail without disturbing the rings, change barrels, then reinstall the scope and ring assembly, the first shot should be within about +/- 2" at 100 yards of zero from the previous setup.
 
Thanks Jerry for the info.

I think we are speaking of different devices as a "range rod". I think you may be referring to an indicator rod, like PTG makes?

My range rod is a 24" rod, with the end machined to fit a spin collet. I hold it in the tailstock, and lay an indicator on it near the breech. I can reach into the barrel a long distance (although resolution degrades the deeper you go)

I then check it with my interapid with long stylus, and so far, the test indicator has been in agreement with the rod.

On the muzzle end, I've been using a mag base and reaching to where the muzzle will end up being, with a test indicator. it's a little bit of a pain and I worry about damaging the indicator, so I need a better system on the muzzle. I need to bolt a small slide table or something near the spider to adjust the indicator.

I know this has been hashed over a lot, but this process is the heart of precision rifle barrel fitting.
 
"feel"

probably the biggest part of chambering no matter what method you use is experience and developing "FEEL" for the reamer and it's cutting characteristics.

chris
 
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