RCBS 7mm Remington Short Ultra Magnum (RSUM) Full Length Die Set

The RCBS 7mm Remington Short Ultra Magnum (RSUM) Full Length Die Set gives reloaders a complete two-die solution for consistently preparing ammunition in this short-magnum cartridge. If you're handloading 7mm RSUM for a bolt-action rifle—whether for hunting or long-range target work—this set handles the essential resizing and bullet-seating operations that keep your ammo safe and accurate.

The Full-Length Sizer Die is the workhorse of the pair. It brings fired cases back to SAAMI minimum dimensions, resizes the case body, decaps spent primers, and expands the neck to ready it for a bullet. The die includes a decapping pin and expander unit built in, and vents are machined into the design to prevent case damage from trapped air and excess lubricant—a smart touch that protects your brass during the sizing stroke. Headspace is held to minimum tolerances, so the case length stays true and doesn't shift during full-length sizing.

The Seater Die completes the set with a built-in roll crimper that secures the bullet as it seats it in one smooth operation. This two-step approach—size and decap, then seat and crimp—is the standard method for 7mm RSUM reloading and the foundation of reliable, safe ammunition.

Key Features

• Full-Length Sizer Die with integrated expander-decapping unit
• Seater Die with built-in roll crimper for simultaneous seating and crimping
• Vents in sizer die prevent case damage from trapped air and excess lube
• Headspace held to minimum SAAMI tolerances for consistent case length
• Designed for 7mm Remington Short Ultra Magnum bottleneck cases

Specifications

Frequently Asked Questions

What's included in this 7mm RSUM die set?

The set includes a Full-Length Sizer Die with an integrated expander-decapping unit and a Seater Die with a built-in bullet seater plug and roll crimper. These are the two essential dies needed to reload 7mm RSUM bottleneck cases from fired brass to finished ammunition.

Does this die set resize and decap in one step?

Yes. The Full-Length Sizer Die handles both resizing the case body and decapping the spent primer in a single stroke, with the expander unit integrated into the die to prep the neck for bullet seating.

Will this die set work for 7mm Remington Short Ultra Magnum?

Yes, this RCBS Full-Length Die Set is specifically designed for the 7mm Remington Short Ultra Magnum (RSUM) cartridge and brings fired cases to SAAMI minimum dimensions for safe, consistent reloads.

Does the seater die crimp the bullet?

Yes. The Seater Die features a built-in roll crimper that secures the bullet while seating it in the case, combining both operations in one stroke for efficient reloading.