Manufacturer: RCBS 39401
Full Length Sizer Dies for bottleneck cases have 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.
All RCBS Seater Dies have a built in roll or taper crimper as appropriate for the particular caliber. To seat bullets without crimping, simply unscrew the die until the crimp ring no longer engages the case mouth.