The Redding 300 Rum Remington Ultra Magnum Type S - Match Neck Die Set (SKU: 38288) is a precision 3-die system engineered for reloading .300 Remington Ultra Magnum (.300 RUM) cartridges. Built with industry-standard 7/8"-14 threading to fit standard reloading presses, this set provides complete control over neck tension, case dimensioning, and bullet concentricity to extend brass life and maximise accuracy.

Key Features

• Type S Bushing Neck Sizing Die: Utilises self-centring, interchangeable bushings (sold separately in .001" increments) to size case necks without overworking the brass, operating with or without the included expander ball.
• Independent Body Die: Restores critical case body dimensions and bumps the shoulder back without altering neck dimensions when chambering resistance develops.
• Competition Bullet Seating Die: Features a micrometer adjustment top calibrated in .001" increments and an internal alignment sleeve with a free-floating seating stem to minimise bullet runout.
• Calibre-Specific Geometry: Engineered exclusively for the .300 Remington Ultra Magnum cartridge firing .308" (7.62 mm) diameter projectiles.

Specifications

• Product Type: 3-Die Reloading Set (Neck Bushing Die, Body Die, Competition Seater Die)
• Calibre Compatibility: .300 Remington Ultra Magnum (.300 RUM)
• Bullet Diameter: .308" / 7.62 mm
• Thread Interface: Standard 7/8"-14 thread
• Micrometer Adjustability: .001" graduations
• Package Weight: Approximately 0.7 to 0.9 kg (1.5 to 2.0 lbs)
• Required Components (Sold Separately): Standard #6 Shellholder (Part #11006) and Redding sizing bushings

Who is the Redding 300 Rum Remington Ultra Magnum Type S - Match Neck Die Set for?

• Long-Range Precision Shooters — Requires the .001" micrometer seating adjustments and self-centring bushing neck control of this 300 RUM reloading die set on standard 7/8"-14 thread presses to eliminate bullet runout and achieve match-grade ballistic consistency.
• High-Volume .300 RUM Brass Handloaders — Relies on this 300 RUM reloading die set to prevent work-hardening on expensive cartridge brass through targeted bushing sizing, while using the independent Body Die to bump shoulders only when needed.

Less suitable for: Handloaders sizing shorter magnum cartridges like the .300 Winchester Magnum or .300 Remington SAUM, which require shorter-dimensioned cartridge-specific die sets, or shooters requiring complete base-to-neck resizing in a single pass after repeated high-pressure firings, who are better served by a dedicated full-length sizing die set.