Recutting 223 Rem standard RCBS dies for Star 11/16-24

[Manuel]

Dave Wilson (aka fc60 here on Starreloaders) took on the project of recutting a RCBS 11101 F.L. Die Set in 223 Rem for the Star toolhead with 11/16-24 die holes.  He did this as a one time project, noting that the RCBS dies were "difficult to machine."  The case hardened thickness of the rifle dies was .015 to .020 inches and that just to get through this hardened layer "ate up several carbide inserts".  He reported however that machining was straight forward once the hardened surface was removed.

The attached pictures attest to the skill of his machine work and he understands the clearances necessary for a die in a Star reloader.

He used as a initial guide the measurements I posted for modifying a set of Dillon standard 223 dies for a 7/8-14 hole head that are posted under "Reloading 223 Rem on Star" here in this forum.

I set the dies up using adapters to reduce the 7/8-14 holes in my toolhead to 11/16-24 to check for clearances.  If the pictures don't look quite right, you are probable seeing the thin knurled ring of the adapter.  It is close but as can be seen in the pictures, there is ample clearance for both the sizer and seater dies.  

[Manuel]

The modified dies functioned fine.  There were no scratch marks on the brass from the cut to shorten the sizer die.  The seater stem was cut short so it cleared the tool head spring anchor screw. The size die was shortened sufficiently (yet still long enough to recess in the shellplate recess on full throw) so that the brass sized to spec in a Wilson case gage. I did use lubricated cases.  I was able to adjust the seater die for the correct overall length and to lightly crimp the brass into the jacked bullet groove.  It measures such that it should headspace fine but I have not yet loaded and test fired.  I'll do this once I set the dies up in a Star toolhead with regular 11/16-24 openings.  My initial goal was to show that standard dies could be cut down and fit in a Star with sufficient clearances to use with 223 Rem case and bullets.

The overall length of the sizer body is 2.253 inches and the diameter at the end is reduced to .640 inches in order to clear into the shellplate.  The seater die body is 2.470 inches in lenght.  If I get another set of RCBS 223 dies (my only set was used for this!), I'll post side by side for comparison. If it will help, I'll be glad to post any other measurements or views needed.

I'd like to hear from those who have cut down dies about cutting through the case hardened layer.  Any trick or method to make it easier?  Is there any brand of die that is not as case hardened or that has a very thin layer?  A less difficult to work metal would be a help.

[333OKH]

The Guys that cut down most Dies, usually use Lee Dies, it could be that they are easier to machine.

[starman]

all you do is OD grind the dies to size then cut the thread or thread grind the thread come on what is the big deal here about rethreading a die