Bushing Die Conversions

Z

Zebra13

Member
Gents,

I have a pile of full-length and neck sizing dies for my varmint guns that are the "old fashioned" kind, meaning no neck sizing bushing ala Redding or Wilson. I'm not a fan of working the ever living snot out of the case necks, so I'm toying with the idea of firing up the lathe and attempting to convert them to accept bushings. Anybody out there done this before, or have any advice on doing same? I have all the tooling (carbide) so...

...or should I just send them all off to Jim Carstenson?

Thoughts and opinions are appreciated,
Justin
 
Justin,

I'm glad you brought this up as I've been thinking about it for a couple of weeks....has to be winter boredom! I bought a couple of "scrap" dies just for this purpose.

I'm sure one of the more experienced members will chime in and say "your're wasting your time", "just buy a bushing die", etc. Well, I have bushing dies but I like learning new things (sometimes the hard way) and am curious if I can do it. Plus it expands my knowledge and I REALLY like that part!

Here's my plan....

-Take a scrap die, mount in 4 jaw chuck. I might start off using a neck die so I can use the go-gauge as a reference point as it will slide easily in and out of the die.
-Roughly center off outside of die for now. Use boring bar to open up die from top so indicator will fit. From what I've read the case hardening is somewhere around .008 thick so it won't take much to get into mild steel which will be much easier to work with.
-Indicate off existing neck using Mitutoyo 513-504 indicator to ensure concentricity.
-Bore to approx .5005 to approximately start of shoulder for placement of bushing. More or less clearance might be ok too, not sure. Use gage pin to test hole size, need to order some laps from them anyhow.
-Bore rest of hole to approx .5312 for threading, leaving recess for bushing to seat.
-Thread to 9/16-18 using tap pushed with live center. We're into mild steel so this should work, I hope.
-Screw in 9/16-18 bolt leaving a little for bushing float
-Put die in press, run a case in and see what happens.

Congratulations, I've now spent 4 hours working on something that may or may not work! :)

I'm down for comments that might help Justin and/or myself out....

Very cordially, BP
 
Have done both ways, sent it to Jim Carstenson and made them myself. Jim does really good work and would have my highest recommendation.

Now if you are bound and determined to do it yourself, you will need carbide cutting tools. The dies are surface hardened and you have to cut thru that hardening. Once you do that, they cut like butta! Should be no problems.

Instead of boring to .5005", take a carbide tool and break the surface of the top of the die in such a way that a 1/2 inch carbide end mill will fit with no play. Now cut until the neck sizing section of the die is gone. Now you can internally thread the thing with a 1/2 " tap. As long as your bushing fits (Redding bushings are .500" OD) in the neck sizing cavity

It's just time on the lathe. Good luck and have fun.

Bob
 
Last edited:
Justin,
I have converted a couple. I use a masonry bit to rough drill out the top of the die, then use a boring bar for the final dimension to accept the bushing. I use Redding’s decapping rod assembly made for their bushing dies. I single point thread the die to fit it to the Redding decapping assembly.
It is a little time consuming to get everything true before starting.

I have never had Jim Cartestensen do any dies for me but have heard good things about him and would not be afraid to send one to him to do.

James
 
I DO MY OWN JUST THE WAY YOU DESCRIBE.......I anneal the top half of die first.....and make my own bushings..... no wait for stuff......
bill larson
 
Actually, the absolutely, positively, best resize die would be the old-style die, but with the dimensions fitted to your chamber. If you're going to go to all the work, why not do it that way?

Downside is you do have to anneal your cases when they get hard & the spring-back changes significantly, but unless you're of the alinwa school, you should that anyway. Affects more than just the neck, you know...

The neck portion of the die should squeeze the neck so that the expander plug -- which you might also have to make -- only opens up the neck by .001 or so. You won't be overworking the brass.

If everything else is right, you'll have the straightest rounds on the bench, and your neck tension will be very, very even.
 
Gents,

Thank you much for your replies, I appreciate it.

My thought, much like Bob's, was to take most of the die material out with a carbide end mill, and than bring it to final dimension with a boring bar. I was going to single-point the threads, but if I won't be losing anything by using a tap, I will probably use one.

A couple of things I'm wrestling with:

How to hold the die. Chuck jaws are rarely, if ever, straight. If I get one part dialed in, I may have the wobblies someplace else. So...I can bore soft jaws or, I was thinking of chucking up a piece of 1.5" aluminum round stock, face it, and drill, ream, and thread to 7/8-14. Screw the die in tight to the locking collar, and away I go. Thoughts?

The other concern is how to accurately measure to the neck/shoulder junction of the die so as to know how deep to bore my bushing orfice. I have an idea, but it involves chanting, gage pins, and an animal sacrafice, so I'm interested in how you guys would do it.

Thanks,
Justin
 
Last edited:
Justin,
For depth I used the dimension from the reamer print for my cartridge, you could use SAAMIs chamber drawings available on line. The dimension of course you are looking for is from the base of the cartridge to the neck shoulder junction.
Measure the depth the cartridge head sets in the press case holder to know how much case actually goes up in the die(seems like that is .200, someone will correct me I am sure if I am wrong). Measure the OAL of the die and calculate the difference. Then you know how far it is from the top of the die to the neck shoulder junction in the die.
When you are done the neck shoulder junction of the die will be somewhat rough and need polishing.

James
 
Zebra13 said:
Gents,

Thank you much for your replies, I appreciate it.

My thought, much like Bob's, was to take most of the die material out with a carbide end mill, and than bring it to final dimension with a boring bar. I was going to single-point the threads, but if I won't be losing anything by using a tap, I will probably use one.

A couple of things I'm wrestling with:

How to hold the die. Chuck jaws are rarely, if ever, straight. If I get one part dialed in, I may have the wobblies someplace else. So...I can bore soft jaws or, I was thinking of chucking up a piece of 1.5" aluminum round stock, face it, and drill, ream, and thread to 7/8-14. Screw the die in tight to the locking collar, and away I go. Thoughts?

The other concern is how to accurately measure to the neck/shoulder junction of the die so as to know how deep to bore my bushing orfice. I have an idea, but it involves chanting, gage pins, and an animal sacrafice, so I'm interested in how you guys would do it.

Thanks,
Justin
Click to expand...

LOL!!!

Until I can make up a jackable backing plate for my lathe chuck or buy one a' them jackable chucks I can't see any way to modify an existing die.

Nor to make a die lest it be all done in one setup.

(And no, before anybody suggests it, I DO NOT mean a "Buck Chuck." I've got those thangkyewyouverymutch!)

al
 
You must log in or register to reply here.
Back
Top