This two-die set is for bottleneck type cases used in tight-chambering semi-automatic, pump or lever-action rifles. It consists of a Small Base Sizer with an Expander-Decapping Unit and Regular Seater Die with Seater Plug. The sizer resizes cases below SAAMI minimums, reducing the shoulder and body by a few thousandths. It also de-primes the case. The included Seater Die has a built-in roll crimper to secure the bullet at the same time it's seated. To seat bullets without crimping, simply unscrew the die until the crimp ring no longer engages the case mouth. Reload bottleneck cases used in tight-chambering semi-automatic, pump, or lever-action rifles Small Base Sizer Die resizes the case to slightly below SAAMI minimums helping ensure reliable feeding and chambering in tight-chambering rifles Expander-Decapping Unit removes spent primers from the case and expands the case mouth to allow for easy bullet seating Component and Caliber Reference Table