The Full-Length Sizer Die brings the case to SAAMI minimum cartridge dimensions. It sizes the outside of the case, de-primes and expands the neck to accept the bullet. The die has vents to prevent case damage caused by trapped air and for excessive lubricant. Headspace is held to minimum tolerances to avoid changing the case body length during full length sizing. Brings the case to SAAMI minimum cartridge dimensions. Sizes outside of case, de-primes and expands neck Vents prevent case damage caused by trapped air and excessive lubricant Headspace is held to minimum tolerances to avoid changing case body length during full length sizing Remember the shell holder! Component and Caliber Reference Table