I only use a light crimp on the cannelure for hot loads in revolvers. I once had a S&W 686 .357 lock up (9gr. unique, 125gr. xtp...way too hot for a S&W!! I now only shoot this load in a Ruger Blackhawk) when a bullet jumped and bound up the cilinder. I've been crimping revolver loads ever since.
I've never used a crimp for rifle ammo.
I've never used a crimp for rifle ammo.
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