The Hornady Custom-Grade New Dimension Bullet Seating Die (.375 Caliber) seats .375 calibre projectiles into rifle cartridge cases to consistent cartridge overall lengths (C.O.A.L.). Built from heat-treated solid steel, this mechanical reloading tool is dimensioned specifically for full-length magnum cases, including the .375 H&H Magnum and .375 Ruger. It features an in-line seating system with a floating alignment sleeve that holds the projectile, case neck, and seating stem in true axial alignment before the bullet enters the case mouth, reducing bullet runout during assembly.

• In-Line Seating Sleeve: Uses a floating alignment sleeve to pre-align the case neck and projectile, maintaining concentricity throughout the seating stroke.
• Integrated Roll Crimp: Allows reloaders to apply an optional roll crimp to secure heavy .375 projectiles into the bullet cannelure, preventing projectile movement under heavy recoil.
• Sure-Loc Lock Ring: Features an Allen-bolt split-collar clamp that grips uniform thread surface area without driving a set screw directly into the die threads.
• O-Ring Tension Adjustment: An internal rubber O-ring maintains friction on the seater adjustment screw for repeatable manual depth tuning.

Product Specifications

• Thread Interface: Industry-standard 7/8"-14 thread
• Calibre Compatibility: .375 Calibre (.375 H&H Magnum, .375 Ruger)
• Shipping Weight: 0.27 kg (approx. 9.5 oz)
• Packaged Footprint: Approximately 32 mm × 32 mm
• Power Requirements: Manual mechanical operation (unpowered)

Who is the Hornady 375 Cal. Seating Die For 375 H&H, 375 Ruger for?

• Handloaders assembling dangerous game ammunition — mounts via an industry-standard 7/8"-14 thread into standard presses to seat .375 calibre hunting projectiles to precise overall lengths while applying a heavy roll crimp against recoil.
• Reloaders targeting heavy big game — utilizes a 0.27 kg solid-steel construction and internal floating alignment sleeve to build concentric, dependable .375 H&H Magnum and .375 Ruger ammunition for water buffalo and scrub bulls.

Less suitable for: Presses using large 1-1/4"-12 threaded die stations without a 7/8"-14 reducer bushing, shooters requiring full case resizing (who require a dedicated full-length sizing die and shellholder set), or precision reloaders seating high-BC polymer-tipped projectiles who require an accessory custom seating stem or a dedicated micrometer seating die.