plumbers lead or railroad babbitt lead, old building roof flashing, I live near a major salmon fishery and rip out tangles of line snagged on the bottom which is loaded with split shots, junkyard wheelweights ( if yo go around with a pail and hammer you can take off the old steel clip weights ) modern glue on weight is zinc mostly. the steel floats to the top in the melt. lead is out there. I cast for centerfire as well as bp and have a luber/sizer that makes for precise cast bullets. Use a hardness tester to ensure density/ hardness and scrap lead becomes useful ( or do a large melt fluxed with beeswax and cast ingots , if you do it right and stir a bit the entire melt will be uniform. Always wear a good respirator because lead vapor is invisible but quite toxic