Bill,

I bought a $50 Turk Mauser with corroded out bore form BIG5 Sporting Goods Store in late 1999.

When I took it apart I was amazed at intricacy of design.

By mid 2000 I had acquired a full sized lathe, vertical mill, oxyacetylene, and two partners and lots more Mausers to sporterize.

Bryant was the one who described on his website the .020" oversized cup to push the tap handle that held the reamer.

http://www.bryantcustom.com/articles/rebarrel.htm



Some gunsmiths on Yahoo gunsmith list answered my questions;

http://sports.groups.yahoo.com/group/Gunsmithing/messages/

And a contributor there posted a picture of his spider lathe for me:

http://members.tripod.com/Rbertalotto/pictures/headstock_spider.html

By late 2002, we were producing [for ourselves] .4 to .5 moa VZ24s with Lothar Walther barrels from Brownell's.

When the barrel was dialed in to within .0002" in the grooves, the cut chamber would eventually be within .001"



But I am an engineer and my two partners are machinists.

They generally did the work, while I found the information on the internet and in books, bought tooling, bought barrels, bought guns, and waved my hands. They hated my metalworking workmanship, and wanted to do everything for me.



So now I built a shop at my house and bought another lathe and mill.



The lathe at my house [1967 Clausing 5914] has a tailstock with so much play, I don't trust is warm OR cold. I have shimmed it up to be parallel with the ways and concentric with the headstock, but the ram is still too loose in the tailstock. I have cut the threads in the headstock and cut the chambered in the steady rest. I was always told, "Once the work is in the lathe, the chuck is not loosened until the work is done."



What does it all mean?

I am no expert, but I can't see why the loose reamer pusher will not work with the breech in the headstock.

What advantage does the steady rest have in cutting the chamber?

Why take the barrel out of the chuck once it is in place?

TIA

Thanks Bill. Love your posts.

TCLouis,
Sorry if I hijacked your thread.
Back to your question.



Here we see a barrel in a 4 jaw chuck.
A test indicator can be used to "dial in" the bore until is is very concentric with the lathe. Notice the copper wire that holds the barrel. That is so the barrel can point in the direction of the spider without flexing.

A 3 jaw chuck may be adjusted for one diameter, but are often .005" off concentric when the jaws and thread are worn.

The other end of the bore can also be dialed in at the spider on the left side of the headstock[again with a test indicator on the end of a magnetic base and arm] to be concentric.

Have I put barrels in 3 jaw chucks?
Yes I am guilty, but with some lathes and new chucks that might only be .001" out, and with pistols, I am not that good of a shot anyway

Some 3 jaw and 6 jaw chucks can be adjusted. But with my second hand 9" 6 jaw Buck Chuck, it is too much trouble to do for every barrel size. Some 3 jaw chucks get soft jaws made from Aluminum that are then cut to be correct for one diameter. That might be a good way to handle production with a large number of like barrels.

What does it all mean?
You have to get the barrel concentric to the lathe.
A straight forward way to do that is with a 4 jaw and a test indicator.

--
A society that teaches evolution as fact will breed a generation of atheists that will destroy the society. It is Darwinian.

3 jaw or 4 jaw chuck?

Steady rest or cinched up close to the jaws of the chuck?

Nosy folks wonder how you do it