Greetings!
If your range / shooting area allows, dig that lead out of the embankment. I'll separate out the very hard "Cowboy Action" bullets from the soft / swaged and jacketed bullets; when I fire up the pot, I'll add the harder bullets to the softer melt a small handful at a time. I like my bullets to be between 13BHN to 15BHN or so for the average CAS handgun and rifle cartridges.
Sorry, I can't be more specific about my lead / tin / antimony ratios; I use my LBT Hardness Tester to give me an idea of where my bullets are. I believe that most factory CAS Ammo is loaded with bullets that are FAR HARDER than they need to be; so, when I dig them up, I use them to harden my melt. Have Fun!
M.T.M.