The 3-Die Taper Crimp Set is for loading straight-wall cartridges. Its steel Sizer Die sizes the case and de-primes. The Expander Die expands the case to the proper diameter to accept the bullet, and it imparts case mouth flare/bell for bullet feeding. The Seater Die seats the bullet and taper crimps. Features a hardened steel Sizer Die (case lubrication required) Expander Die to properly expand case to accept bullets Taper Crimp Seat Die for proper cartridge headspacing Standard 7/8"-14 Thread Proprietary Die Steel Component and Caliber Reference Table