The Hornady 00-7 Small Primer Cup (MPN: 390005) is a factory replacement priming sleeve engineered for Hornady bench-mounted single-stage reloading presses. Machined from solid steel, this mechanical component mounts directly to the press priming arm assembly to capture and align an individual small primer during the ram stroke. It supports standard Small Rifle, Small Pistol, and Small Magnum primers, seating each primer square into the cartridge primer pocket without tilting, binding, or damaging the anvil. It operates alongside the Hornady Small Primer Punch (MPN: 390034) and Primer Seater Cup Spring (MPN: 390007) to maintain proper seating depth and mechanical alignment on Hornady 00-7, Pro-Jector, and Lock-N-Load Classic presses.

Key Features

• Precision Primer Guidance: Bored specifically to fit standard 0.175 in (4.45 mm) small primer diameters, preventing flipped or tipped primers during press-stroke seating.
• Machined Steel Construction: Built from durable steel to withstand repeated mechanical pressure without flaring, burring, or deforming under normal bench-reloading conditions.
• Single-Stroke Press Priming: Designed for single-stage manual loading, cycling one primer per stroke directly on the press ram assembly.
• Direct Factory Fit: Serves as an OEM replacement for lost, worn, or damaged primer cups on legacy 00-7 and contemporary Hornady single-stage priming arms.

Specifications

• Brand: Hornady Manufacturing
• Manufacturer Part Number (MPN): 390005
• Product Type: Small primer seating cup / sleeve
• Material: Machined steel
• Compatible Primer Diameter: 0.175 in (4.45 mm) nominal (Small Rifle, Small Pistol, Small Magnum)
• Capacity: 1 primer per press stroke
• Item Weight: Under 15 g (0.5 oz)
• Press Compatibility: Hornady 00-7, Hornady Pro-Jector, and Hornady Lock-N-Load Classic single-stage presses
• Associated Components: Hornady Small Primer Punch (MPN: 390034) and Primer Seater Cup Spring (MPN: 390007)
• Power Requirements: None (purely mechanical)

Who is the Hornady 00-7 Small Primer Cup for?

• Handloaders servicing or converting single-stage presses — installs into the priming arm to seat small primers with a 0.175 in (4.45 mm) diameter, restoring factory alignment or converting the press from large-primer setups.
• Sporting shooters reloading precision rifle or pistol ammunition — provides single-stage mechanical primer alignment tailored to 0.175 in (4.45 mm) primer pockets, seating each primer individually on the press stroke to avoid crushed anvils.

Less suitable for: Cartridges requiring large primers with a nominal diameter of approximately 0.210 in (5.33 mm), which require a dedicated large primer seating cup, as well as progressive shuttle-feed systems and third-party press rams that require proprietary tool-specific primer slides.