The Redding 0.2225 Expanding Mandrel (Model #21502) is a precision handloading component designed to set uniform case neck internal diameter (I.D.) on .22 caliber cartridge cases. Manufactured from CNC-machined, hardened tool steel with a precision-ground finish, this mandrel establishes 0.0015 inches of theoretical neck tension when seating nominal 0.224-inch diameter projectiles. By sizing the neck from the inside out, it eliminates variations caused by brass neck wall thickness inconsistencies and promotes uniform bullet seating resistance across cartridges such as the .223 Remington, .22-250 Remington, .22 ARC, and .220 Swift. The mandrel requires a Redding Precision Expanding Die Body for press mounting and operation.

Key Features

• Internal Neck Uniforming: Directly expands the interior neck wall to 0.2225 inches, delivering consistent bullet grip and release pressures across fired or new brass.
• Self-Centering Alignment: Built with an angled mating surface that seats directly into the Redding Precision Expanding Die body to preserve concentricity and minimise neck runout.
• Tapered Entry Profile: Features a smooth nose transition to expand brass necks gradually without buckling or deforming thin-walled case necks.
• Tool Steel Construction: CNC-machined from hardened, precision-ground tool steel with the exact diameter roll- or laser-marked on the head for rapid identification.

Product Specifications

• Manufacturer Part Number: 21502
• Mandrel Diameter: 0.2225 inches
• Target Bullet Calibre: .22 Calibre (nominal 0.224-inch bullet diameter)
• Resulting Neck Tension: 0.0015 inches
• Material: Hardened tool steel
• Mounting System: Redding Precision Expanding Die Body (7/8"-14 press compatible)
• Power Requirement: 0V (manual reloading operation)

Who is the Redding 0.2225 Expanding Mandrel for?

• Precision rifle reloaders loading .224 inch caliber cartridges — sizes case necks to an exact 0.2225 inches diameter, ensuring a uniform 0.0015 inches of bullet grip to maintain consistent seating depth and release dynamics on .224-inch loads.
• Benchrest shooters seeking minimum case neck runout — relies on a self-centering alignment design inside the die body to expand neck internal diameters to 0.2225 inches without introducing concentricity errors or runout into pre-sized brass.

Less suitable for: Handloaders seeking heavier neck tension for magazine-fed semi-automatics (requiring 0.002 to 0.003 inches of grip), who require smaller 0.2220-inch or 0.2210-inch mandrels; shooters seeking ultra-light single-feed tension, who require larger 0.2230-inch or 0.2235-inch mandrels; non-.22 calibre cases, which require calibre-specific mandrels; or unsized brass cases whose fired internal neck diameter has not first been sized below 0.2225 inches using a bushing or full-length sizing die.