I recently found 3.5 # of Goex 1 1/2 X black powder. I would like to try some duplex loads in our Browning high wall. I have both 4227 and 4759 powders. I have the Lee 405 grain pb mold, and could cast some in 20 to 1 or 25 to 1 alloy? I have been ready old posts on duplex loads and have the Lyman Cast bullet handbook. hc