developing a good .303 cast bullet

[mdeland]

Well my two last attempts at lathe boring both a PP and GG .303 bullet have been failures as both have Key holed at 50 meters. I think I'm going make and try a cherry mold next as it's so hard to fabricate tools that won't shaft flex and still be able to get in these small holes and cut proper diameters. Measuring I.D.'s is also very tough without specialized tools in these .30 caliber molds.
On the last bullet I tried a NASA design but got the base band to thin I think as it is key holing , I'm guessing it is because the base is not sealing the bore. I need to recover some of them to tell for sure.