I purchased some lead from a guy who cuts keels out of sail boats i plan to use for muzzleloading bullets. The lead is plenty soft and i have fluxed it several times but it takes 850 for it to pour a decent looking bullet and decent fill out using a TC aluminium mold. Do i need to add a little tin? It seems like its a little too "thick". I have a RCBS 20lb pot so how much tin would i need to add to get a thinner more consistent flow.Its diffucult to pour it into a round ball mould with that itty bitty hole.Thanks for any help!