Some more thoughts
If you buy cast or swaged Lead bullets, you do not have control of many factors. There are at least two more conditions Lead bullet buyers can control that can prevent a lot of Leading, one is avoiding using undersized bullets. Gasses blowing past the bullet will cut significant amounts of Lead off the sides of the bullet, and deposit it in the bore. Groove diameter varies between barrels, especially in older firearms. It would be good to slug your barrel to find groove diameter.
It would be nice for Lead bullets to be slightly larger than groove diameter for your barrel. This would cause faster sealing of the throat just ahead of the chamber. I cast/lube/size to .001" or .002" larger diameter, and I cast them hard. Some people like to use soft bullets and very fast powders, hoping that if the bullets are at or a little small for groove diameter, they will "slug up" to whatever diameter is required (this has not worked for me, except with dead soft bullets and black powder in muzzleloaders).
In semi-autos, the cast bullet you need, when seated in the case, may increase the diameter of the cartridge to the point where you do not have free chambering of the cartridge. The only thing you can do then is use jacketed bullets. Gas blow-by with a small bullet does not remove significant amounts of jacket material.
Buying a heavy Lead bullet will mean your velocity will be lower, which also reduces the likelyhood of Leading.