You realize you need pure lead for muzzleloader casting.Lee makes a lead hardness tester.Can you easily scratch the fishing weights with your fingernail?Wheel weights are much harder to mark.I aquired about 300lbs of lead from old pipe wrap at a local hospital that would have cost them afortune to get rid of as it's considered a hazardous waste.Plumbing companies salvage scape lead from old job sites that they upgrade.Try them.Don't mess with old car batteries as these are more dangerous than they are worth.[acid/chemicals etc...........].54 conials Lyman/TC Maxis you get 15 rounds per lb of lead more for a 230gr ball no doubt.I've just got into this myself but it's not too hard to learn.You can start out with a Lee electric pot that holds 10lbs or a simple gas camp stove and casting pot.Lots of fun and cheaper than buying factory projectiles............harold