Because I have 1/2 dozen WSMs from 6mm through 300, and purposely mutilate my brass on a regular basis, and the Rsaum does not come any where near the speed or amount of firings they WSM based cases get, I have never owned one but I use to load for a shooting buddy and he and the cases gave up after a while. plus there was a really bad dry spell for that brass. and like most with a short attention span he went on to something else and never looked back.
Dean
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