The Redding Case Mouth Expander Die – .45-70 U.S. Government (Item 93209) is a dedicated straight-wall rifle reloading die designed to open the internal case diameter and create a uniform flare (bell) at the case mouth. Machined from high-grade alloy steel on precision lathes, heat-treated in atmospherically controlled furnaces, and hand-polished, it functions as the critical second stage in standard 3-die reloading workflows. By expanding sized brass to accept .458-inch nominal diameter projectiles, it prevents case shaving, scraping, and base deformation while ensuring concentric bullet alignment during the seating process.

Key Features

• Straight-Wall Expansion: Expands the internal neck diameter and flares the case mouth of .45-70 Government brass to ensure smooth bullet entry.
• Projectile Protection: Eliminates lead shaving and jacket deformation when seating cast, coated, or jacketed bullets.
• Precision Construction: Machined from heat-treated alloy steel and hand-polished for smooth mechanical operation and uniform neck tension.
• Standard Thread Mounting: Integrates into single-stage and progressive reloading presses using the industry-standard 7/8"-14 thread interface.

Specifications

• Calibre Compatibility: .45-70 Government (.458" nominal bullet diameter)
• Thread Interface: 7/8"-14 thread
• Expander Plug: Redding Expander Plug #99457
• Shellholder Compatibility: Standard Shellholder #18 (part #11018)
• Material: Heat-treated, hand-polished alloy steel
• Power Requirements: None (manual/mechanical press operation)

Who is the Redding .45-70 Government Expander Die for?

• Lever-Action Rifle Enthusiasts — Requires a 7/8"-14 thread expander die to process straight-wall .45-70 Government brass across standard single-stage and progressive reloading presses.
• Australian Big-Game Hunters — Relies on precise case flaring for .45-70 Government brass to seat .458-inch projectiles cleanly for hunting pigs and deer without deformed case mouths.
• Cast-Bullet Handloaders — Uses the dedicated .45-70 Government expander die to create an exact case mouth bell that prevents lead shaving and coating damage during projectile seating.

Less suitable for: Presses requiring non-standard 1-1/4"-12 threads or custom arbor-style interfaces without thread adapters, or bottleneck precision handloaders requiring micro-adjustable .0005-inch step neck tension, who are better served by dedicated match-calibre mandrel expanding dies.