I never have with BP loads, Matt, but have with nitro-for-black loads, 7625 specifically. I used the little plastic ball buffer that is sold by Precision Reloading, if I remember correctly (PB ?). I used a Mylar wrap inside the hull and and a Tyvek disc on top of the shot to prevent leakage of the buffer out of the crimp. Are you wondering if the black powder might melt the buffer somehow?

SRH

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