The Redhawk has a very long cylinder and chambers, so it'll work best with the bullets seated out and crimped in the lower groove (closest to the base of the bullet), which gives more room for powder and allows for slightly heavier charges for higher velocity while staying at safe pressure levels. Plus the bullet doesn't have to jump as far to the forcing cone/rifling, so accuracy should be a bit better, but you'll have to determine what is working best in your gun. The loads I listed are for the lower crimp groove BTW, and I should have mentioned that, so I'll edit my post above to reflect that.