CH4D Swage tool. Best money I have ever spent.
Yep.
But use it in conjunction with a quality shell holder.
Lee shell holders do not qualify. They're too sloppy, and designed to work with too many cartridges of "similar" rim dimensions - but not similar enough to be ideal for any
one of those cartridges.
Lee shell holders allow most cases to tip substantially when used on the CH4D primer pocket swage tool, resulting in an incomplete or completely ineffective crimp removal. And one of the worst shell holders in the bunch just happens to be the Lee #4 (.223/5.56), because it is designed to also work for .32 revolver cartridges which have thicker rims, larger diameter rims, and larger case bodies.
Just use a quality shell holder.
My preference is for Hornady, if I have one for that rim size (Hornady shell holders are the most consistent that I have measured, with closer tolerances than most). If there isn't a Hornady, then I reach for whatever else there is from Redding, RCBS, Lyman, Wilson, Forster, CH4D, Pacific, Bair, and on down the line...
Bottom line: not Lee.