RCBS Full Length Die Set - Group A - Popular Rifle Cartridge .30-378 Wby Mag

The RCBS Full Length Die Set for .30-378 Wby Mag (Group A) is a precision two-die reloading system designed for handloaders working with bottleneck magnum rifle cartridges. This full length die set consists of a Full-Length Sizer Die with integrated Expander-Decapping Unit and a Seater Die with Bullet Seater Plug. The full length sizer die resizes fired cases to SAAMI minimum cartridge dimensions, simultaneously de-priming the case and expanding the neck to accept loaded bullets. Built-in vents in the sizer die prevent case damage from trapped air and excess lubricant, protecting the integrity of your brass across repeated reloading cycles.

Headspace is held to minimum tolerances to ensure consistent chamber fit and reliable ignition. The seater die allows precise bullet seating depth adjustment, critical for magnum cartridge performance where slight variations in seating can affect pressure curves and velocity. This two-die reloading setup is engineered for the .30-378 Wby Mag, a magnum rifle cartridge known for extreme velocity and long-range capability. The dies accommodate the full length sizing demands of bottleneck cases and are constructed to handle the chamber pressures associated with magnum rifle ammunition. Each die is individually fitted to ensure proper function and consistent results across production reloading.

This set is intended for serious rifle reloaders who load for magnum cartridges, whether for precision target shooting, long-range hunting, or competitive rifle disciplines. Hand loaders working with the .30-378 Wby Mag require equipment capable of managing the dimensional demands of this high-capacity magnum case. The RCBS Group A die set provides the controlled sizing and seating precision necessary to produce ammunition that maintains the velocity and accuracy potential of the .30-378 cartridge. SKU RC29501 (MPN 29501) is the authoritative identifier for this specific die set configuration.