The Redding .336 Heat-Treated Steel Neck Sizing Bushing (MPN: 73336) gives precision handloaders exact control over case neck tension and bullet grip without over-working the cartridge brass. Machined with a standard 0.500-inch outer diameter and a 0.375-inch height, this bushing floats freely inside compatible bushing-style sizing dies to self-centre over the case neck, preserving case-to-bullet concentricity. It is hardened to Rockwell C 60–62 and features a micro-polished internal sizing surface to minimise friction and prevent brass marring during the sizing cycle.

• Precise Neck Tension Control: Sizes the exterior of the cartridge neck to an internal diameter of 0.336 inches (8.534 mm), setting bullet tension without requiring an internal expander ball.
• Extended Brass Working Life: Sizing only the neck exterior prevents excessive working and fatigue, substantially improving case longevity.
• Floating Self-Centring Design: Floats inside the die cap during operation to ensure self-alignment over the cartridge case neck.
• Heat-Treated Alloy Steel: Hardened to Rockwell C 60–62 with a hand-polished interior to deliver smooth, consistent sizing cycles.
• Die Compatibility: Fits all Redding Type S Bushing Full Length Dies, Type S Neck Sizing Dies, Competition Bushing Neck Sizing Dies, and standard 1/2-inch L.E. Wilson bushing dies.

Specifications

• Manufacturer Part Number (MPN): 73336
• Internal Sizing Diameter: 0.336 inches (8.534 mm)
• External Dimensions: 0.500-inch (1/2") outer diameter; 0.375-inch (3/8") length/height
• Material & Hardness: Heat-treated alloy steel, Rockwell C 60–62
• Internal Finish: Hand-polished
• Weight: Approximately 10–15 g (packaged weight ~45 g / 0.1 lbs)
• Power Requirements: None (mechanical reloading accessory)

Who is the Redding .336 Heat-Treated Steel Neck Sizing Bushing for?

• Precision rifle handloaders loading large-bore or magnum cartridges — Targets loaded neck diameters of approximately 0.337 to 0.338 inches (such as .300 Win Mag, .300 PRC, or .300 Weatherby Magnum) by providing an exact 0.336-inch internal sizing diameter to establish 0.001 to 0.002 inches of bullet grip.
• Competitive shooters aiming to preserve case-to-bullet concentricity and extend brass life — Utilises a 0.500-inch outer diameter floating design within Rockwell C 60–62 hardened alloy steel to size cartridge necks concentrically without over-working the brass or requiring an internal expander ball.

Less suitable for: Handloaders seeking to size clean brass without external lubrication, or those reducing neck diameters by more than 0.004 to 0.005 inches in a single step; these applications require Titanium Nitride (TiN) coated neck sizing bushings or intermediate sizing steps with stepped bushing sizes to prevent brass galling and shoulder collapse.