Thanks for describing your method. I have heard other methods described that gave what I would describe as less than desirable results, and too many tales of attempts at extreme camming over, trying to achieve the impossible.
Do you find that it is desirable to use one brand of shellholder over another? Redding advertises their shellholders as being hardened. In your experience, are they the only ones, or are other brands hardened ? I can see the virtue in modifying an unhardened piece, both in ease of processing and in the results.
"Extreme camming over" cannot work - it is silly - it would require that you can compress the steel in the die body, which you cannot.
All you do when you "over cam" is to stress and stretch the frame of the press.
I use RCBS shell holders (though I am not an RCBS fan)... because when I was a dealer, I wound up with a million of them. They are Okie dokie - Redding shell holders are very good, and the Bonanza shell holders (before they were bought up by Forster) are great!
All of the above shell holders are hardened. I don't know about LEE (yuck!).
You take a piece of #800 Silly cone carbide "Wet n dry" paper, and put it on a plate of glass - oil it, and put the shell holder on it and start going in a figure "8" on the paper. Rotate the shell holder in your fingers by 90° every minute, so you won't lap a slope in the shell holder.
You can do it by trial and error - you will take down about 1 thou a minute (at least I did). Lap down the shell holder a little, wipe off the black stuff, and try a case in the die, then the rifle... do this every minute or two until the bolt closes on the case the way you like.
Make sure to mark the shell holder with a red "sharpie" pen or something... or put it in a zip lock bag so it doesn't get mixed in with the other shell holders.
23 thou was the most I have ever had to do - the rest were 6 to 12 thou.
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