RCBS Full-Length Die Sets are crafted from proprietary die steel and precision-machined to exacting tolerances, ensuring top-tier performance for hand-loaders. Each set is designed specifically for reloading bottleneck cases and includes a Full-Length Sizer Die with an Expander-Decapping Unit and a Bullet Seating Die with a Seater Plug. The Full-Length Sizer Die sizes the case to SAAMI minimum cartridge dimensions, de-primes and expands the neck for proper bullet seating. Vents are incorporated to prevent case damage from trapped air or excess lubricant. Additionally, the die maintains precise headspace tolerances to avoid altering the case body length during full-length sizing. The Seater Die features a built-in roll crimper that securely crimps the bullet while seating it, ensuring reliable ammunition every time.