The RCBS 9550 Universal Primer Arm-2 handles both small and large primers, making it a practical choice if you're loading multiple cartridge types on the same press. Swapping between primer sizes takes less than 60 seconds—just change the plugs and sleeves that come in the kit—so you're not fumbling with tools or losing momentum at the bench. It's built to fit Rock Chucker II, JR, Reloader Special, and most C-frame presses, giving you broad compatibility across the popular RCBS press lineup.

If you're already running one of those presses and want to avoid buying a dedicated primer arm for each caliber family you reload, this dual-size setup cuts down on bench clutter and changeover time. It's straightforward reloading infrastructure—no fancy engineering, just a component that does what it's supposed to do so you can focus on the rest of your process.

Not compatible with RC Supreme presses, so verify your press model before ordering. The arm seats primers consistently across rifle and pistol cartridges, supporting the precision that accurate handloading demands.

Key Features

• Seats both small and large rifle and pistol primers
• Includes primer plugs and sleeves for both sizes
• Fast changeover—swap sizes in under 60 seconds
• Fits Rock Chucker II, JR, Reloader Special, and most C-frame presses

Specifications

Frequently Asked Questions

Which RCBS presses will this primer arm fit?

The 9550 works with Rock Chucker II, JR, Reloader Special, and most C-frame presses. It is not compatible with RC Supreme presses. If you're unsure about your press model, check the manual or the press nameplate before ordering.

Do I have to buy separate arms for small and large primers?

No. This single arm handles both small and large rifle and pistol primers. You swap between them by changing the plugs and sleeves, which are included and take less than 60 seconds to swap out.

What comes in the box?

The kit includes the primer arm, plugs, and sleeves for seating both small and large primers.