The Redding Boss Reloading Press (MPN 72100) is a heavy-duty, single-stage O-frame reloading press engineered for precise resizing, decapping, bullet seating, and priming of rifle and pistol cartridges. Constructed from a rigid cast-iron frame, it eliminates structural flex under heavy full-length sizing loads to maintain critical case concentricity and low runout. Featuring a frame offset at 36 degrees along with an offset compound leverage handle, this press provides reloaders with direct workspace visibility and manual hand clearance. The manual mechanical system requires no electrical connection, utilizing a positive-stop compound linkage and a smart primer arm assembly supplied with both large and small priming arms.

Key Features

• Rigid Cast-Iron O-Frame: Delivers high structural rigidity to eliminate frame flexing during high-pressure resizing operations.
• 36-Degree Offset Design: Positions the frame and leverage handle at an angle to offer clear visibility into the case mouth and unobstructed manual access.
• Compound Linkage with Positive Stop: Reduces mechanical operating effort while enforcing uniform ram travel depth across sizing and seating operations.
• Smart Primer Arm System: Moves automatically in and out of the ram pathway during cycling, allowing priming at the bottom of the stroke for enhanced physical feel.
• Universal Tooling Support: Interfaces with industry-standard 7/8"-14 threaded dies and rotatable, snap-in universal shellholders.
• Spent Primer Catcher: Includes an integrated collection system to route spent primers cleanly away from the workspace.

Specifications

• Press Type: Single-stage "O"-frame
• Frame Material: Cast iron
• Frame Offset Angle: 36 degrees
• Frame Opening: 4.0 inches (approx. 101.6 mm)
• Ram Stroke: 3-3/8 inches (3.375" usable stroke)
• Die Threading: Standard 7/8"-14
• Shellholder Compatibility: Standard universal snap-in shellholders
• Bench Mounting: 3-hole mounting pattern requiring 5/16" bolts
• Power Requirements: Manual mechanical operation (no electrical power required)
• Weight: 14.6 lbs (approx. 6.3 to 6.6 kg)

Who is the Redding Boss Reloading Press for?

• Precision Rifle Reloaders — Requires a 14.6 lbs rigid cast-iron single-stage press to eliminate frame flex under heavy sizing loads, maintaining exact concentricity and low bullet runout across match-grade handloads.
• Moderate-Batch Handloaders — Requires a 4.0-inch frame opening and 3-3/8 inches of ram stroke combined with standard 7/8"-14 die threading to manage handgun and standard-to-magnum rifle cartridges up to .300 Win Mag and .375 H&H at production paces of 50 to 100 rounds per hour.

Less suitable for: Handloaders loading extra-long or ultra-magnum calibres that exceed the 4.0-inch frame window (such as .338 Lapua Magnum or .50 BMG), who require a larger-window single-stage press (4.5-inch opening or dedicated 50-calibre frame); or high-volume reloaders requiring output exceeding 50 to 100 rounds per hour, who require a progressive reloading machine.