SAC Modular Sizing Die – 7 PRC

“So why is this design any better?”

“The Modular Sizing Die” has a unique design where the cartridge’s body geometry is sized by the die body, the cartridge’s shoulder and neck geometry are sized by a “Neck/Shoulder Bushing”. This allows one die body to be used for the whole cartridge family.

Furthermore, the Modular Sizing Dies are precision machined with the main focus of properly sizing your fired brass. Our resizing dies will size the base of the cartridge slightly more than the shoulder.

After studying precision CNC machines and tooling, we designed the Precision Resizing Die to utilize a series of shallow tapers, not threads to properly center and secure the Solid Decapping Pin. Our tapered geometry offers unparalleled concentricity and repeatability.

Last but not least, we designed the cartridge sizing geometry to size a little more at the base and a little less at the shoulder when compared to most resizing dies on the market. In properly sized rifle chambers, this helps eliminate extraction issues of fired brass. Our shoulder sizing geometry and helps minimize case runout and over working of the brass by not sizing the shoulder too much.

Modular Sizing Die Assembly….

Modular Sizing Die Body: Standard 7/8 x 14 threads, 17-4 Stainless Steel, Special Salt Bath Nitride finish for increase lubricity and performance compared to standard Salt Bath Nitride.

Knurled ER11 Top Cap: ¾ x 24 Threads tighten the Knurled ER11 Top Cap into the die body, compressing the supplied ER11 collet which properly secures the Decapping Pin or Expander Mandrel ensuring the utmost concentricity. Use the wrench flats when more torque is desired to secure the Solid Decapping Pin or Expander Mandrel.

Taper Adapter: When the Knurled ER11 Top Cap is threaded into the die body, it seats the ER11 Collet into the Taper Adapter, in turn securing the Decapping Pin. The Taper Adapter sits directly above the Neck Sizing Bushing, allowing the Neck Sizing Bushing to float.

ER11 Collet: Commercially available ER11 collet to secure a variety of Decapping Pin and Expander Mandrel diameters.

Solid Decapping pin: Designed to be slightly smaller than bullet diameter, the Solid Decapping Pin WILL NOT expand sized necks, however, will fix dented necks, increasing neck uniformity. Utilizing a .058” nominal diameter pin tip to fit in small primer flash-holes. The Solid Decapping Pin can be set to any pin tip protrusion or by simply adjusting the wide mouth retaining clips position.

Neck/Shoulder Bushings: Available in many caliber specific neck diameters, but also be custom made to “wildcat” cartridges, or change the caliber of the cartridge reloading for. Special .001” shims can be placed above the “Neck/Shoulder Bushing” and the “Taper Adapter” to adjust headspace without threading the die in or out.

To set up your Short Action Customs resizing die, please follow these initial.

• Ensure the inside of the resizing die is clean and free of debris. We like to use a 40 caliber plastic pistol brush with a 12 ga. Shotgun patch to patch out the inside of the die body.

• Select and install the appropriate shell holder. We headspaced our resizing dies to work with standard Redding or RCBS shell holders. Redding Competition Shell Holders as well as Forster Co-Ax press shell holders work well also.

• With the reloading press ram all the way up, thread the resizing die into the top of the reloading press and continue to thread down until the die body touches the shell holder. Next, lower the ram and thread the die down slightly enough to achieve a little bit of “cam over” with the press. Tighten down the die body lock ring.

• Using a headspace comparator that contacts the shoulder of the brass, establish the fired brass headspace. Next, lubricate a piece of clean, fired brass and cycle it through the Short Action Customs resizing die in a smooth, consistent ram stroke.

• Measure your sized brass and compare it to the fired brass. We recommend reducing the headspace of the fired brass .001”-.002” for most shooting applications. In order to increase or decrease sized brass headspace. Thread the resizing die body into the press more, or less. The use of Redding Competition Shell Holders is also recommended. Another way to adjust headspace is to remove or install custom shims between the “Neck/Shoulder Bushing” and the “Taper Adapter”.