RCBS Full-Length Die Sets are crafted from proprietary die steel and precisely machined to stringent tolerances, ensuring the highest quality for hand-loaders. Each set includes a Full-Length Sizing Die and a Bullet Seating Die, designed specifically for reloading bottleneck cases. The Full-Length Sizer Die features an Expander-Decapping Unit, which sizes the case, de-primes and expands the neck to fit the bullet. Vents in the die prevent damage from trapped air or excess lubricant. The die also maintains minimum headspace tolerances to avoid altering the case body length. The Seater Die is equipped with a Bullet Seater Plug and built-in roll crimper to securely seat and crimp the bullet in one step.