Facing breech end of tapered barrel on a lathe

Geesh, here's the setup:

Barrel for a 788 Remington, straight shank near chamber (@1.250") and in about 1.5" (or less), it starts to taper down to .750" at the muzzle.

I need to face the breech end to get correct head-space. Oh, snap. A nice straight barrel would be much easier to indicate... Had thought of turning between centers, but it will be difficult facing the breech near the tailstock center.

I measured the bore, and it is large enough for the barrel to enter deep enough so the straight shank can be held by the jaws of my Adjust-Tru chuck.

Uh, how am I to support the barrel in the headstock? Looks like making a spider for the outer end of the bore...

Once I do mount the spider, I just indicate off the barrel?

Three spider holding screws, or four?

Any pertinent comments?

Reply to
Louis Ohland
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Standard practice is to hold it between centers, after making a breech plug and center-drilling it for the tailstock center.

The muzzle end should be driven with a drive dog on a drive plate.

The primary reason my uncle bought the big-bore SB 10L (which I now own) was to have a big enough spindle hole to hande rifle barrels. If you want to hold the breech end in a chuck (4-jaw preferred) for facing, with a steadying/centering plug in the outboard end of the spindle, and if you have a big enough bore to handle the barrel, it will save you some setup time.

Reply to
Ed Huntress

No help I am afraid, but I have noticed most of the lathes sold as "gunsmith" lathes have spiders on the back side of the spindle bore already. While I have no idea of the quality you might look at the two gunsmith lathes offered by Grizzly for some inspiration. Sadly I watch Mike Scheerz from Gila River Gunworks do barrel work many times and I never really paid much attention. Never figured I would have a machine I would consider doing that type of work with. Heck I watch him shave the breech end of my rebarreled Mauser to adjust head space and I couldn't tell you how he did it. LOL.

Reply to
Bob La Londe

Ed, I was going to hook up my automatic retracting compound, so that every time the lathe dog comes around, the tool holder retracts... Don't you have yours?

Makes facing the breech at the headstock so easy...

Reply to
Louis Ohland

Here's how Grizzly does it:

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Three screws are miserable to adjust as they interact in two directions.

I use a cut-down drill chuck to hold thin stock centered, or at least keep it from whipping around. Since the stock holds the drill chuck in place axially it doesn't need to be attached to the spindle. It makes a good handle to pull the stock out of tight collets.

jsw

Reply to
Jim Wilkins

Noooo....

If you have a big enough bore, you don't have to worry about it -- just chuck the thing -- but it's been 20 years since a rifle barrel has been mounted in my lathe.

Reply to
Ed Huntress

All you need to steady the barrel in the outboard end of the spindle is a plug, which ordinarily is turned to fit on the lathe.

Reply to
Ed Huntress

Reply to
Louis Ohland

If you're doing gun work for a living or a full-time hobby, I'm sure they're nice. If you're doing one once in a while, you can make a bushing-type plug in less time than you can place an order for the spider.

I use them all the time for fishing rods, too. Just split them down one side, or make two saw slits at 90 deg., 3/4 of the way through from the small end. I prefer maple but oak is OK. Get the taper right and they'll hold themselves in place with a light tap from a mallet.

Reply to
Ed Huntress

I would like to see how you do that.

Reply to
Bob La Londe

After 'Glee'. I don't have a good recording of this ep yet.

Reply to
Jim Wilkins

Lets see if this HP photo editing program works better than Nero 6 to crop and resize:

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The nose was stepped down to slide into the 5C collet closer tube. The handwheel blocks a chuck key so I pressed in the spokes to tighten it. I popped off the shell and gear and and opened up the threaded mounting hole (eraser end) to 1/2" clearance. The steel machines very nicely, almost like

12L14.

jsw

Reply to
Jim Wilkins

Not sure I understand how that is going to support the other end of a gun barrel through the spindle. In fact even for smaller stock I only see it working if you have a thin wall hollow draw bar. Am I even close?

Reply to
Bob La Londe

I have done similar work on M1917 and Mauser 98 and 95 barrels with the barrel between centers. The breech end is in the tail stock on a half center so I can face the end all the way to the chamber. Lots of lube on the half center.

David

Reply to
David R. Birch

I'm answering Bob's private e-mail here.

The chuck holds up to 1/2" round stock and wouldn't help with the larger barrel. I don't have trouble with 3/8 and larger stock whipping around because it doesn't have to spin as fast as thin rods.

For my lathe a 1-1/4" pipe coupler seems the right size to bore to a close sliding fit onto the left end of the spindle and tap for four screws to make a centering spider for >1/2" stock, should I ever need one.

I usually screw pipe fittings onto a well-made pipe nipple to machine them, and first turn the OD concentric with their existing threads so the fitting will center in a 3 jaw chuck. Brass pipe works well for this, the 1/2" stuff I have fits a 13/16" collet. I borrow brass reducing bushings to adapt it to larger sizes from the pipe tap drawer where they protect the cutting edges.

jsw

Reply to
Jim Wilkins

If it's chambered, you can use plugs and do it between centers. Unchambered, you can use a half-center on the breech end.

If your headstock has a big enough bore, you can use a 4-jaw and indicate off a plug. Use a 4 screw spider and that end isn't really THAT critical, dog it down enough so it isn't whirling around and you can get close enough on that side by just indicating off the outside of the barrel. I suppose even a wood bushing on the off end would do the job if you could keep it from creeping loose. A spider can be made from a chunk of pipe that can be machined to a slip fit over the spindle plus some set screws to hold it in place. An afternoon's job if you take your time.

Stan

Reply to
Stanley Schaefer

I've tried/used a lot of different image programs through the years for this. I have yet to find any that can do better than Irfanview and RIOT. Use Irfanview to crop the image and then RIOT to optimize the file size/compression. If you just need to optimize the compression/file size RIOT can do that on its own. The author plans on adding a crop feature sometime in the future.

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If you have/use Irfanview you may already have the "lite" version. Check the "File" menu for item "Save for Web... (PlugIn)" entry. There is also a standalone version available at the RIOT website and the full version plugins for Irfanview, Gimp and XnView.

Reply to
Leon Fisk

Thanks, but I only want to crop and reduce the resolution, mainly due to my own dial-up connection. The HP program that came with a camera seems to have done that. Many of those were posted from an older PC with a different program, ArcSoft IIRC.

jsw

Reply to
Jim Wilkins

Louis Ohland wrote in news:AK3Pq.28107$ snipped-for-privacy@newsfe22.iad:

I did a Springfield barrel a while back. 4 jaw chuck, and instead of a spider I cut four long wooden wedges. I adjusted the wedges until it ran true by eye, and then tweaked the breech end in with the four jaw & a dial indicator.

Doug White

Reply to
Doug White

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