The Hornady #12 Precision Shell Holder (Mfg Part #: 390552) is a precision-machined, heat-treated solid steel reloading accessory engineered to grip cartridge case extractor grooves firmly during high-force resizing, decapping, and priming strokes. Built to fit industry-standard universal T-slot press rams, it provides single-case alignment and smooth, snag-free case insertion across single-stage presses, turret presses, case trimmers, and hand-held priming tools.

Key Features

• Precision-Machined Heat-Treated Steel: Constructed from solid steel to withstand high-leverage full-length resizing forces without bending, shearing, or expanding tolerances.
• Radius and Chamfer Lip Profile: Features a wide-mouth opening with a subtle entrance radius designed to facilitate smooth, snag-free case insertion and extraction.
• Universal Press Interface: Standard single-station footprint fits universal ram slots across major bench reloading systems including Hornady Lock-N-Load, RCBS, Lyman, Lee, and Redding.
• Bench Tool Compatibility: Directly fits dedicated reloading bench accessories, including the Hornady Cam-Lock Case Trimmer and Hand-Held Priming Tool.

Specifications

• Material: Heat-treated, precision-machined solid steel
• Nominal Rim Diameter Envelope: .421" to .422"
• Compatible Cartridges: 6.8mm Remington SPC / 6.8 SPC II, .224 Valkyrie, .25 Remington, .30 Remington, .32 Remington, .351 Winchester Self-Loading (.351 WSL), 8mm Nambu
• Press Compatibility: Single-stage and turret presses with standard universal T-slot rams (Hornady, RCBS, Lyman, Lee, Redding)
• Operating Capacity: Single cartridge per press stroke
• Approximate Weight: 30 g to 45 g

Who is the Hornady #12 Precision Shell Holder For 6.8mm Rem Spc And .40 S&W for?

• Handloaders reloading 6.8mm Remington SPC bottleneck cartridges — Secures cases within the dedicated .421" to .422" nominal rim diameter envelope to prevent case head slippage during resizing in this reloading press shell holder.
• Handloaders reloading .224 Valkyrie precision ammunition — Delivers exact single-case retention across the .421" to .422" rim dimension required for uniform shoulder bump and neck sizing on this reloading press shell holder.
• Reloaders utilizing standard single-stage and turret reloading presses — Mounts directly into universal T-slot rams across 5 major press platforms (Hornady, RCBS, Lyman, Lee, and Redding) to process single cases with .421" to .422" rim diameters.

Less suitable for: High-volume progressive press setups requiring a multi-station Hornady #12 Shell Plate (part #392612), cartridges with .473" rim diameters such as .308 Winchester that require a #1 shell holder, or cartridges with .378" rim diameters like .223 Remington that require a #16 shell holder.