Case Trimming on Lathe

[Thumb]

I'm getting ready to start prepping a couple thousand 223 & 22-250 cases and was thinking about doing the case trimming on my lathe but I can't find any kind of chuck or adapter to be able to quickly change from case to case.

Anyone out there do their trimming on a lathe and have a suggestion on what I could use?

 

[Jay Christopherson]

Make yourself a bushing that indexes on the shoulder (using the chamber reamer). Then figure out a way to mount that busing on a tool holder on your tool post. Mount your trimmer (forster, end mill, whatever) in the chuck, adjust the bushing/tool to whatever depth you want, and go to town. No case holder required, just feed the cases by hand into the bushing and you'll get a precise trim. And it'll be fast as you can work.

Here's an example of one way to do it, that I used to use:

 

[Thumb]

Thanks for that tip, sounds like it will work great. I'll see what I can come up with.

 

[jonbearman]

Good idea Jay,you now have a gracey/Giraud for the cost of a little ingenuity.Good job.

 

[Erik Cortina]

Good idea Jay,you now have a gracey/Giraud for the cost of a little ingenuity.Good job.

And a lathe.

 

[Jay Christopherson]

Good idea Jay,you now have a gracey/Giraud for the cost of a little ingenuity.Good job.

And a lathe.

lol, yes, but the trimming fixture is incidental to the lathe. If I didn't have a lathe, I'd have a Giraud for sure.

 

[jhord]

http://www.littlecrowgunworks.com/wft.html

Essentially the same thing as Jay suggests, if you don't feel like making the tooling. I use them for 3 different cartridges and I can't think of any way of trimming faster. I saw an ad where somebody now offers a micrometer head version, that would be pretty slick.

 

[stool]

I USE A SHOULDER BASED CUTTER in the lathe and use a wilson case holder to hold the case.
a pc of hardwood 1x4 across the ways to knock the case in and out

 

[ridgeway]

Power drill Lyman or RCBS case trimmer. All utilize a quick case change work holding mechanism. A few thousand, maybe invest in a Dillon rapid trimmer?

 

[Thumb]

I've looked at the dillion trimmer and it seems it would do the job but I was thinking since I had a lathe I could save some $$.

 

[Erik Cortina]

Well, I have two lathes and I still bought the Giraud trimmer.

 

[suberjc]

Well, I have two lathes and I still bought the Giraud trimmer.

+1 on the Giraud

 

[Thumb]

Well, I have two lathes and I still bought the Giraud trimmer.

and too much extra money! J/K

If the lathe idea doesn't turn out to do the job then I'll think about the Giraud when and if I get the extra $$$

 

[ireload2]

Use a Wilson case holder with a 1" 5C collet.
Install an internal stop in the collet to stop the case head against.
Trim to a fixed carriage stop with a a tool bit of your choice.

 

[stool]

i need to do a bunch of 223 for my biz.
i normally use a shoulder based cutter in the lathe with a wilson case holder in my hand...but for some strange reason the the tool has become unobtainium.....
so being a big dillon fan i sprung for another 550b and their case trimmer to process my brass thru....

OK WHAT THEIR SALES TEXT DOES NOT SAY is their "trim" die portion of the setup is a full length sizing die also sizes the neck...WAY THE F**K UNDER SIZE!
the one way to almost ensure crooked necks is to pull a button thru them........i use neck bushing on nearly everything i do.

when i say way under size i mean WAY UNDER SIZE.....AS IN 10 THOU PLUS NECK TENSION....
$800 PLUS dollars in a tool that ruins brass !
i took their die and using high speed on my lathe and a small carbide bring bar, opened the neck up....this took a sub .0005 setup to keep the necks straight.
so far it looks good...but boy was i one pissed off customer when i discovered their "trim" die was a sub standard SIZING die.