Thread: Has anyone ever run tests on a belted magnum collet resizing die (before and after)

Greetings All,
I believe that the die is to iron out the bulge that develops just in front of the belt when the cases are FL resized to just bump the shoulder slightly. Due to the somewhat sloppy tolerances with some belted chambers this leaves the bit right in front of the belt unsized and even bulges it a bit making chambering hard. I believe that the die only sizes the area in front of the belt but not having seen one could be wrong. A standard FL die should take care of the area behind the shoulder. The tighter nature of many current chambers may be making this less of a problem.
Regards Grandpamac.