The Redding 39263 Steel Size Button is an original equipment manufacturer (OEM) replacement expander component designed for Redding bottleneck rifle sizing dies. Manufactured from precision-machined, heat-treated steel, this expander button installs onto the die decapping/expander rod assembly to set consistent internal case neck diameter and uniform neck tension during the sizing stroke. Its tapered profile ensures smooth entry and extraction from the case mouth to minimise brass stretching and neck runout across standard single-stage and progressive reloading operations.

Key Features

• Internal Neck Sizing: Expands fired cartridge case necks to the exact internal diameter required for proper bullet seating tension.
• Tapered Steel Profile: Smooth transition design reduces friction, neck runout, and brass distortion as the expander passes through the case mouth.
• Direct OEM Replacement: Sized specifically to replace worn, damaged, or misplaced expander buttons in standard Redding die assemblies.
• Die Compatibility: Fits Redding standard Full-Length sizing dies, standard Neck Sizing dies, and Type-S Bushing dies configured for bottleneck cartridges.
• Mechanical Operation: Fully manual reloading component requiring no external power or electrical connections.

Specifications

• Brand: Redding Reloading Equipment
• Manufacturer Part Number (MPN): 39263
• Material: Precision-machined, heat-treated steel
• Calibre / Diameter Specification: .264 Caliber / 6.5mm (compatible with 6.5 Creedmoor, 6.5x55mm Swedish, 6.5-284 Norma, 6.5 PRC)
• Compatible Die Types: Redding Full-Length Sizing Dies, Neck Sizing Dies, and Type-S Bushing Dies

Who is the Redding Steel Size Button for .264 Cal / 6.5mm Reloading Dies for?

• 6.5mm Precision Rifle Competitors — requires uniform internal neck diameter and consistent bullet grip across .264 Caliber / 6.5mm cartridge brass to maintain tight velocity spreads and shot-to-shot consistency.
• High-Volume Handloaders Maintaining Redding 6.5mm Die Sets — relies on a dedicated .264 Caliber / 6.5mm factory steel replacement expander button to restore correct sizing function to existing Redding bottleneck dies without replacing the entire die assembly.

Less suitable for: High-volume reloaders who run unlubricated case necks; this steel expander button requires inside-neck lubrication during operation to avoid neck galling, making free-floating carbide size button upgrade kits or dedicated neck-sizing bushing systems better suited for lube-free neck expansion.