I don't cast lead bullets but figure I have shot over 100,000 of them downrange. My understanding is even "hard cast" lead is softer (or maybe more pliable is a better description) than a jacketed or plated bullet of equal diameter. Everything I have read states lead bullets create less friction (heat) traveling down the barrel. Loading manuals show slightly lower charges for lead than jacketed of the same weight. Lots of information is available about alloying and casting lead bullets. The consensus seems to be that its the sizing of bullets not their hardness that causes leading in bores. Makes sense to me, bullets are round, not polygons, old fashioned lands just squish the lead in a bit but the polygons have little concave triangles the lead can fill. BTW leading generally is only an issue when you switch back to harder plated or jacketed rounds. People shoot lead through Glocks, they just clean them really well afterward to remove any lead from the bore. Anyway, I shoot lead in .32/.327 .38/.357/9 .30-30/7.62 and so far the only damage done has been to targets.

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