I picked up this mold recently from a forum member, and made a short run of 30 boolits in 13 BHN hardness (small % antimony). Lubed with 50-50 Alox-beeswax and applied a gas check, they weigh around 176-177 grs; I loaded each over 23 grs of Reloder 7. Didn’t size these, just wiped on the lube by hand - they run .309 to .311 from the mold, front band smaller than rearmost band.
I fired them from a Marlin 336 “waffle top” half magazine rifle, which my dad bought new in the early 1950’s - it sports a 6x Leupold now. It has a 24” barrel and slugs .308 with four grooves (no Microgroove). It will easily shoot under an inch at 100 yards with jacketed 150 gr pills.
Best 5 shot group with the cast slugs was 1-1/4” center to center at 40 yds and the group was about three inches to the left. There was zero unburned powder in the bore - not one kernel left. I can also see a small amount of lead near the muzzle and no soot on the end of the barrel.
Two questions:
1) Would increasing the hardness help with the leading, especially since it appears the lube is petering out before the boolit exits the barrel? Every cast design I shoot in other calibers leaves grease on the muzzle and I don’t get any visible leading, so this is bothering me a bit. We plan to use this load in 3 different rifles as a full power hunting round for feral hogs and deer.
2) Does anyone use a similar mold from another maker that carries more lube? I like molds from Accurate and Tom has a bunch of designs that look interesting.