Reamers, solid or floating pilot

[3sixbits]

Randy Ketchum, a much better smith than me, grinds a spud to within .0002" of the bore, gimbles the breech, and and dials in both end of the barrel so that the bore is concentric to the lath and co- linear where the chamber will be. He assumes that all barrels are bent.

He assumes correctly! Doing what Randy Ketchum does would be great if you have a tool post grinder. Lacking a good Doall, we all get by with a tool like Greg Tannel sells, not as perfect as what you describe.

I want you or anyone else to realize something about all this precision work. It's great and right to do the best you can, but it's still just one more part of the rest of the effort, to "makem shoot".

 

[Clark]

Greg Tannel of Gre'Tan Rifles and Dave Kiff at Pacific Tool and Gauge had their names come up as sources for tapered rods in this thread 4 years ago:
http://forums.accuratereloading.com/eve/forums/a/tpc/f/9411043/m/478100121?r=478100121#478100121

My brother got a Do All tool post grinder at a used store for $10, and thought he was buying it for .1 cents on the dollar, but the old ones go for cheap on ebay.


That thread was a spin off of one I participated in, where "BS" and "precision" got both used more in one thread than anywhere else I have seen for a while:
http://forums.accuratereloading.com/eve/forums/a/tpc/f/9411043/m/352101021?r=754101121#754101121

 

[3sixbits]

It seems that these discussions always end up as a, who's got the longest di_k contest.

I have a brother-in law that long ago gave up working on guns, the Man is a top machinist working in the aerospace industry.

He figured out that it takes more than just precision machining to build a rifle that really shoots.

You have to learn what counts and what not to spend your time on. Working in mills is a neat thing to talk about, but in truth, has vary little real world effect on accuracy.

The reasons have more to do with the environment the machine is set up for. Nc is a whole different ball game, than what any of us will or have a need for.

There are things you can do to your manual lathe or milling machine to make it much better using some of the parts used on these machines that have a great benefit to us, but they ain't cheap.

 

[CentrePunch]

Clark,
the reason why you could not get the pilot of your 30 cal reamer down the PH barrel is because they are designed to shoot British spec Nato 7.62x51 Sniper ammo which utilise a nominal bore size of .298"-.299" and a grove dia of .307"
All barrels for target rifle shooting are made to these diamentions
Formal Target rifle Shooting in the Uk,alomst identical to US Palma style)relies on issued ammo to take out any mechanical advantage in the rifles used, and this ammo is 7.62 Nato RG. Greenspot Sniper Grade.

Ian.

 

[CentrePunch]

3sixbits,
thanks for the advice buddy much appreciated.
A little research has shown me that here in the UK, using a floating reamer holder is the prefered way of those who use the "through the headstock" method of chambering and the through the headstock method is the preferred way of those that are not trained machinists, maybe they dont like the idea of getting their knuckles to close to the revolving chick jaws

Ian

 

[butchlambert]

3sixbits,
What does wear on the ways have to do with a chambering job? Can you do as accurate a chamber job in the steady as in the headstock? Can you tell me how you do it?
Butch

 

[3sixbits]

Assuming you use the tail stock to drive the reamer into the barrel, I think it would be rather obvious that wear in the area where the apron has been used for the greatest number of years would be rather easy to see. I know I see a dip of the tail stock when I move my tail stock towards the head. Heck in this old war production board lathe of mine you can even see movement in the apron,vertical) the closer you get to the head.

For the guy that feels like he has the world by the tail with his gear driven lathe and thinks this is the perfect way to chamber through the head. Try this trick, take your pin gage set, some Dye Chem layout fluid, coat a small pin and let dry, chuck it. Now dry to cut the layout fluid off, without changing the dimension of the pin.

It can be done on a belt drive, but not able to do it on a gear driven lathe? I wonder why that might be? Try it, and you will see the results on the pin.

Odd the things you learn in a good trade school, and from the old machinist over the years.

Kinda of reminds me of a bet I lost one time. An old machinist,dye maker) bet me he could cut solid carbide with a band saw blade, I knew this was going to be easy pickens,I figured he had drank his lunch) and tossed down a hundred bucks feeling the guy would back off. It was almost worth the hundred to see it done.

"Even a blind hog, finds an acorn once in a while"!

 

[butchlambert]

3sixbits,
You didn't answer any of my questions. You don't hold your reamer in the tailstock do you?
Butch

 

[treeman]

so, how did he cut carbide/bandsaw blade?_____treeman

 

[3sixbits]

I use the quill to feed the reamer. When I bought this lathe, I thought I would be able to ream through the head, the spindle bore id is 1 and 5/8ths". That did not workout because of the ways had a lot of wear. My next step was shopping for somebody to rework the ways. Seemed every time I heard about somebody they were either dead or had moved. That's when Bob Brackney showed me how he did it and told me who had taught him. I had known Roy Dunlap for many years and respected him, and he did it the same way. So I figured rather than loading this old lathe on the back of my truck and hauling it back east to have the ways re-worked at the factory. I just do it the way I knew would work.
I don't know where you read a post my me that said that this was the only way to ream a chamber? I do it this way because, for me on my old lathe it works for me!





treeman:

He used the back side of the blade and increased the speed of the saw. I thought he was going to use some special blade and cutting fluid. Heck no, we walked over to the band saw, he turn it on, increased the speed and promptly started in the cut on the back side of the blade. Within 30 seconds, I could see, I lost my money.

 

[butchlambert]

3sixbits,
All the more reason to use the headstock. You are only using the ways to cut a real short tenon. If you use a pusher or floating reamer holder, you don't care if the ways are worn out. If you indicate the bore properly, drill, bore, and ream everything will follow your bored hole. Bob Brackney is a great smith. You still haven't told me your setup, just that you use a steady rest. How do you hold it in the lathe and how do you indicate your bore in the steady rest. I did not say you couldn't do it several ways, but how do you set up and indicate to do a good job? Do you put your reamer in a drill chuck in the tailstock?
Butch

 

[Clark]

There are steady rest guys and there are headstock guys, like there are tablesaw guys and radial arm saw guys.

My brother has chambered 10 times and always in the headstock.

I have chambered 15 times and did half with the headstock and half with the steady rest. I have a foot in each canoe.

I push the reamer with a drill chuck arbor in the tailstock, while holding the reamer with tap wrench. I feel the torque on the tap wrench handle with my finger and turn the wheel on the tailstock at a rate that keeps the torque on the reamer down to a few inch pounds. After .050" or so, I pull the reamer and clean off the chips with a mixture of motor oil and gasoline with a toothbrush. Then I put some Sulfured cutting oil on the reamer and put it back in the chamber.

When I am done chambering, I put the test indicator in the chamber and measure concentricity.
.001" is good, but the bore had to be concentric with the lathe for that to mean anything.

 

[3sixbits]

Sorry to have taken so long to reply. I had to take a work break.

Yes I turn between centers, yes I use a live center in the tail stock to push off the center drill hole in the reamer, using the quill to feed and a wrench to keep the reamer from turning.

I'm no longer an active benchrest shooter in competition. That means I'm not trying to sell anything to anybody else. I don't have a web site up and running to pedal my products or myself.

The reason I do what I do, is because it works for me. What you do to get whatever results, more power to you. I flatly do not care for one vary important reason. I KNOW BETTER!

 

[butchlambert]

3sixbits,
I will not ask you again as I am not getting an answer. I don't chamber barrels for a living, only for my satisfaction. I thought you might have a reason for doing it between centers and I could learn something. I enjoy a lively give and take. I did not say what my method was and why I thought that it was better. The only statement that I made was the ways do not figure into a chamber job.
Sorry if I upset you as I only wanted answers.
Butch

 

[CentrePunch]

Butch,
Get hold of a copy of the book: "The Complete Illustrated Guide To Precision Rifle Barrel Fitting" By John L. Hinnant.
It will show you with the use of precise engineering drawings and detailed text, the "Steady" method of chambering, turning and threading a barrel tenon, much easier then i could describe it on this forum.
Its a great book.

Ian.