Home Forums Reloading Bullet Casting What diameter do cast bullets perform well

.002 over bore diameter is a great starting place. Some rifling will want a little bigger and some will want a little smaller. So unless youre chasing the smallest possible groups, the Lee Sizing Kits work for all calibers except 44 Magnum (Need at least .431 for good accuracy) and maybe 300 BO (I use a .309 sizer only for 308 bores).