Modify rimmed cases

[firearmdoc1]

I developed a wildcat cartridge based on a 348 winchester case for use in a custom
Hi-wall that I built. Now what I want to do is modify the 348 case by turning the rim off and cutting an extractor groove. My question is how should I go about holding the cases in the lathe for turning. Of course I want the cases to run true before turning, without the need to indicate each one individually.
Any thoughts, suggestions, or experience with this would be greatly appreciated.
Thanks
Jesse

 

[hotrodlouie]

Use aluminum round stock, machine the bore taper the depth you want the case to stick out, then machine the O.D. in one set up. If you have a good 3 jaw the bushing should repeat 0 run-out when you chuck it up each time.

 

[firearmdoc1]

Hotrod,
If I was to bore a "chamber" for the case, how would I go about holding the case without it spinning when I try to turn the rim off? Are you suggesting a collet of sorts, or am I just over thinking this?
Thanks

 

[hotrodlouie]

If you bore the taper correct and a light tap on the case into the bore it should not spin in the bushing. Done this before you tap to hard it is tough to remove. Hope this helps

 

[firearmdoc1]

I have a re-size reamer for this, would it be advisable to use it for this? What you posted last makes perfect sense to me. I appreciate your input.

 

[jsn]

Can you use a collet? How about an LE Wilson case trimmer as the holder?

 

[firearmdoc1]

Jsn,
Do you know if Wilson sells a case trimmer that will fit the 348 Winchester case?

 

[jsn]

Wilson has one on their web site for fire cases, which means it's good for fired and new/FL sized.

Midwayusa.com carries them but is out of stock:

http://www.midwayusa.com/product/791964/le-wilson-trimmer-case-holder-30-348-winchester-348-winchester

Grafs.com shows one in stock:

http://www.grafs.com/retail/catalog/product/productId/9824

Good luck.

Edit: After rereading your post I was assuming you only wanted the holder to put in your lathe chuck per your OP--they have trimmers too.

 

[firearmdoc1]

I may have to get one of those case holders. It may be the easiest way to go about this. What I am trying to do is make a rimless version of my wildcat for use in a bolt action.

 

[jsn]

What hodrodlouie was suggesting was making your own out of aluminum, same principal.

 

[firearmdoc1]

I probably will try to make my own to srart. Worst case is that it won't work, but it will be a good project.

 

[firearmdoc1]

Turned an aluminum bushing today and tried to turn the rim off a case and cut an extractor groove in it. Everything went well, now I just have to refine my tool bit a little. I would like to be able to remove the rim and turn the extractor groove all at one time.