Well... I have entire discintinued using lead cast bullets. Ive tried everytbing I could possibly try and narrowed it down to the lead melting on the feedramp and jamming up my gun.. Plus its very dirty and is a pita to clean.
I shoot lead almost exclusively in my .45s. (Casting my own is the only way I could afford to shoot .45.) I've never had anything like this happen.
Leading with properly lubed bullets is minimal.
"As was the man of dust, so also are those who are of the dust, and as is the man of heaven, so also are those who are of heaven. Just as we have borne the image of the man of dust, we shall also bear the image of the man of heaven. "