Let's make a better expanding die

V

VZerone

Active Member
Ian you anneal the LEE sizer dies then they cut like butter. Think about it you don't need it to be super hard for just expanding the case neck.

Well when you switch out the turret heads can't you switch out modified expander die?

If you threaded your 99 barrel you can make those Forster bodies and tops.
 
Ian

Ian

Notorious member
Here's what Brad and Fiver were going for, I think? There would have to be a step at the bottom of the sleeve and lip on the bottom of the die to keep the insert in place. Lee rifle charging and universal expanding bodies have a step in them already that would be suitable. I heated a Lee 6.5x55 die full-cherry-red and cooled in lime so I could more easily enlarge the neck with sandpaper, it had no effect on hardness as far as I could tell. Sure did crust up the insides, though.
 

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V

VZerone

Active Member
My cherried red hot air cooled LEE sizer dies were very soft and easy to lathe with a HSS tool bit. Maybe you shouldn't have put it lime LOL don't k now.

Using that LEE sizer die if it wasn't long enough it's very easy to mig/tig weld a section of tubing on it. That what I do.
 
V

VZerone

Active Member
I also have a early expander die I made from some die and drilled the closed end and tapped it for a 7/16ths fine thread and made a bunch of expander plugs from 7/16ths fine thread bolts. Have a whole can of plugs. I switched over to the RCBS expander die because I felt it was a tad more accurate. Plugs from 22 caliber up to 45 caliber and everything inbetween.
 
fiver

fiver

Well-Known Member
you could also use modified Hornady seating dies.
they have the sliding sleeve and the top unscrews.

I almost think locking the case in place and then pressing the spud down into the neck might be your best bet.
unfortunately I also think it would still depend on the straightness of your press.
 
4

4060MAY

Active Member
I use a LEE Collet die
cut the end off till the brass protrudes
When the neck is sized, the mouth of the case remains at the chamber diameter
If you must crank the case to the pin, I suggest making pins to the dia you need
I shoot mostly single shots and there is no need to crimp the end
if the bell on the mouth absolutely has to be removed I use a LEE FCD adjusted for the brass I am using
picture shows protrusion on a 32-20 case, dies that I modified
 

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M

M3845708Bama

Active Member
fiver said:
I was kind of thinking that if AL's bushings could be used in the die body a stem is all you'd have to make.
further making the project easier.
you can't neck size down and expand up at the same time, physics won't allow that.
but if you held the shoulder from rocking and went over a longer tapered expander you could take a lot of the wobble out for sure.

the best way to do this might be to press the case in a solid rest and then come down with the expander into the neck.
for that you'd want the die to screw down on a C shaped piece with a mandrel that come down a tunnel kind of like a bullet puller collet only with a longer handle.
Click to expand...

Almost need to use a lee collet type die rod with one of the other dies. The lee has the pin that goes through flash hole that would get you a lot closer to the alignment you are looking for. If you did not mind a little extra effort to prove improvement, run them through a lee collet die first and then through your regular die. That should resolve neck parallel issue with case. I had also started using a set of Redding dies and got the long taper expander bushing and put it on the neck sizer only die--works well because it doesn't tend to through neck out of alignment.
 
Brad

Brad

Benevolent Overlord and site owner
Staff member
Ian said:
Here's what Brad and Fiver were going for, I think? There would have to be a step at the bottom of the sleeve and lip on the bottom of the die to keep the insert in place. Lee rifle charging and universal expanding bodies have a step in them already that would be suitable. I heated a Lee 6.5x55 die full-cherry-red and cooled in lime so I could more easily enlarge the neck with sandpaper, it had no effect on hardness as far as I could tell. Sure did crust up the insides, though.
Click to expand...
No need for a lip inside. Use a little circle of wire like Hornady does to keep the sliding sleeve in their seating dies.
A groove around the bottom of the die, a hole in the groove at one point. A fine spring wire bent in a partial circle with one end bent at 90°. Bent end protrudes thru hole to keep sleeve from falling out. Rest of wire acts as a spring to keep wire in the groove.
Quite an elegant solution really.
 
Brad

Brad

Benevolent Overlord and site owner
Staff member
Look at the bottom of the die, you can see what I am talking about.
 

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Ian

Ian

Notorious member
Keith used something similar to retain the H-dies in his push-through conversion.
 
Ian

Ian

Notorious member
4060MAY said:
I use a LEE Collet die
cut the end off till the brass protrudes
When the neck is sized, the mouth of the case remains at the chamber diameter
If you must crank the case to the pin, I suggest making pins to the dia you need
I shoot mostly single shots and there is no need to crimp the end
if the bell on the mouth absolutely has to be removed I use a LEE FCD adjusted for the brass I am using
picture shows protrusion on a 32-20 case, dies that I modified
Click to expand...

The more I mull this over the more brilliant I realize it is, for certain applications anyway. The end wouldn't even have to be cut off, just tapered, giving a supported bellmouth to the case. The only downside is the collet dies themselves give exactly zero case body alignment, and with off-center flash holes they can actually be forced a little crooked. That issue is easily fixed by the judicious use of a fired case, modeling clay, and steel-filled epoxy to make a centered support from the bottom of the collet all the way up to where the finger slits begin. It would also remove one die from the tool head.
 
V

VZerone

Active Member
Well I made one this evening. I used a 308 barrel stub for the internal sleeve. I grooved it for the retainer ring. I bored the bullet passage so it would let the expander pass through and also to the right depth so the case shoulder would fit the datum in the chamber and also let a slightly belled case mouth pass. I turned the expand base diameter to precisely mate with the bored hole in the sleeve. There is no way this thing could expand a case neck crooked. Can't wait to try it out.

I tell ya, the Forster seater die system is the way to go, it's benchrest quality in it's expanding duty.
 
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I

Intheshop

Banned
Just a note to say,it wasn't till I took the time to make up a concentricity gage/fixture that was used to find where,in the loading process,that the problem was being created.....things as simple as stacked tolerances.Just clocking the shell holder showed up on above gage.

So,find a die that supports the body with perfect,and confirmed alignment with press centerline....then introduce a sliding expander pin in the neck,and here's the trick,with the fewest parts that have the highest degree of repeatable accuracy. Easy to say,but you need "fewer" parts,not more.
 
Ian

Ian

Notorious member
VZerone said:
Well I made one this evening. I used a 308 barrel stub for the internal sleeve. I grooved it for the retainer ring. I bored the bullet passage so it would let the expander pass through and also to the right depth so the case shoulder would fit the datum in the chamber and also let a slightly belled case mouth pass. I turned the expand base diameter to precisely mate with the bored hole in the sleeve. There is no way this thing could expand a case neck crooked. Can't wait to try it out.

I tell ya, the Forster seater die system is the way to go, it's benchrest quality in it's expanding duty.
Click to expand...

You know the rules of the internet, pictures or it didn't happen! :rofl:

How did you make the expander connect to the rod?
 
Ian

Ian

Notorious member
Rick said:
Yep, this! ^^^^^^^
Click to expand...

With the sliding-sleeve system for full support, you have two moving parts that affect the case, and they can be fitted very closely to each other.

One weakness with the RCBS cast bullet expanding system is number of parts and poor engineering. The spud screws on a rod, sloppy fit. The rod threads through a short threaded section in the top of the die body, very sloppy fit. The tiny jam nut doesn't really pull things straight, more like pulls them crooked. The only way to make it work right is back the spud all the way up against the top of the die so it's bottomed-out and supported there, then you might have to grind the die body down for shorter cases. The spud eventually works loose on the tiny stem threads unless you use threadlocker on them. Too many parts that are too weak for the job.
 
Elkins45

Elkins45

Active Member
This is interesting. One source of inaccuracy is that you are trying to align on a moving object that is unsupported on the sides until the ram reaches the end of the stroke and the case has finally fully fit into the tapered space that receives it. For maximum concentricity you really need it to be a two step process. Step one is the case being fully aligned into the die, and step two being the expander entering into the fully supported and centered case neck. So the expander button just floats above the case neck until the ram stops and then you give it a whack with a hammer, or pull down on a lever that pushes the expander into position.

Adds another step, but nothing would be more precise and you could totally control alignment.
 
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