I make up 30 BR brass but don't shoot one or load for it.(Yet ;D) But I do load for a 6.8 BR Wildcat that I had a reamer cut for.
I use Forster Bushing Bump dies and by changing the bushings to the size I need, I can load for my 22BR, 6mm BR, and the 6.8 BR, all out of the same die.
That same die will go down to 17,20 or just about anything based on the BR case just by changing bushings.
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