A cast lead bullet properly fitted to your firearm using an alloy that will withstand the loads pressure / velocity as well as using a suitable lube and you should not have any leading. Over 35+ years of reloading and casting I can count on one hand the number of times I've had a leading issue, once I figured out what was causing it and fixed it leading was never an issue anymore and that was long before I ever started powder coating my own bullets.

A good read on leading and it's causes.
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