The .224 Valkyrie cartridge is designed specifically for use in AR-15 rifles, so the reloader of this new long-range round would do well to add the RCBS .224 Valkyrie AR Series Full Length Die Set to their reloading bench. This setup is designed specifically to load ammo used in modern sporting rifles, featuring a small-base sizer die and a taper-crimp seater die, all designed to ensure that reloaded ammo chambers easily and reliably in AR-style firearms.