Wish I could give you a direct answer. A few hardness data points. 58 cal Minnie Balls always dead soft. 45/70 40/65 for BPC Silhouette 1/25 about average. Smaller bores like 32/40 1/20.

New wheel weights worthless, most have a lot of other metals. I only cast with pure lead alloyed with pure tin.

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Boats