20 Gauge Slug recommended lead hardness for hunting?
Here in Illinois we are required to hunt deer with slug guns, pistols and muzzleloaders. I've cast for handgun rounds for target shooting based of Lyman Cast Manual wheel weight formula using bar solder to add tin. I've cast for muzzleloader using soft lead pipe. I've been working on a slug load that shows consistent performance over a chronograph, although I have yet to bench shoot it for accuracy from my H&R ultra slug topped with a 4x ERR Leupold.
My questions are; What lead hardness should be used in a slug for deer hunting? Should I use the soft lead for expansion upon impact and be worried about base deformation or use the handgun formula so the base doesn't deform then worry about expansion. Does lead hardness make much difference for hunting purposes?
I own a lathe. Would it be worth making a new pin for the mold that would allow for a thicker base so I could use soft lead?