I'm shooting a RRA AR15 in .458 SoCom.

So far I've had my most best groups with the 325 GR. FN GC boolit using 32.5 GR. W-296 This boolit actually comes out of my mold @ 312 GR. after sizing to .459. I'm casting hard and using Gator GC.
1/4 lb of lead in 5 rounds...

Jack