Measuring cone style sure grip?

When I was a kid, I had my small ends milled down too. I did not shim it though during assembly. I didnt know about the procedure, just observed them bottoming out from the wear pattern and observed that removing from the small end would allow the sides to grip again.
My sg occasionally would not lock, probably cause of lack of shims. B4 milling the cones, it never locked.
I would give it a fair amount of mill so you can have a long life left on the cones. Eventually the cones bore out the carrier and I have no idea if they make larger cones to compensate for that.
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