The Redding Conventional Neck Sizing Die is a precision reloading tool engineered exclusively for .300 Winchester Short Magnum (.300 WSM) brass. Constructed from precision-machined, heat-treated case-hardened alloy steel, this die resizes only the case neck to seat standard .308 in (7.82 mm) diameter bullets while leaving the fire-formed body and shoulder dimensions unchanged. By avoiding unnecessary working of the brass case walls, it prevents work-hardening, significantly extends case life, and maintains the custom-fire-formed fit of the cartridge to a specific rifle's chamber for optimal bullet-to-bore alignment.

Key Features

• Targeted Neck Resizing: Resizes only the neck area of fire-formed cartridge brass, preserving the fire-formed shoulder and body geometry of your specific rifle chamber.
• Extended Brass Longevity: Eliminates continuous overworking of the case body and shoulder, reducing brass fatigue and preventing premature case head separation.
• Integrated Decapping and Expanding: Features a decapping rod assembly (#23307) to punch spent primers and a standard steel expander button (#40307) to establish uniform internal neck tension on the press up-stroke.
• Universal Press Mounting: Uses standard 7/8"-14 threading to fit single-stage and progressive reloading presses across major reloading equipment brands.
• Durable Construction: Machined from heat-treated, case-hardened alloy steel to withstand repeated reloading cycles without dimensional drift.

Specifications

• Product Model: 81223
• Calibre Compatibility: .300 Winchester Short Magnum (.300 WSM)
• Bullet Diameter Compatibility: .308 in (7.82 mm)
• Die Thread Interface: Standard 7/8"-14
• Material: Heat-treated case-hardened alloy steel
• Compatible Shellholder: Redding #6 shellholder (Part #11006 / Competition #11606, sold separately)
• Included Components: Die body, decapping rod assembly (#23307), steel size button (#40307), decapping pin, knurled lock ring

Who is the Redding Neck Sizing Die for .300 WSM for?

• Precision bolt-action hunters — who reload fire-formed brass dedicated to a single .300 Winchester Short Magnum (.300 WSM) rifle and require a neck sizing reloading die that threads into standard 7/8"-14 presses without altering the custom chamber-fit body dimensions.
• Long-range target shooters — seeking to maximise brass longevity and internal neck consistency for .308 in (7.82 mm) bullets by using this neck sizing die to avoid work-hardening the case body and shoulder across high-volume firing cycles.

Less suitable for: Cartridges sharing brass across multiple rifles, rounds used in semi-automatic, lever-action, or pump-action firearms, or cases experiencing heavy chambering resistance; these scenarios require switching to a full-length sizing die or small base resizing die to bump the shoulder and restore factory body dimensions.