Prime with a Die? RCBS Ram Priming!

We’ve looked at a number of priming methods including bench-mounted, progressive, and hand priming systems. Did you know you can prime on any press with the RCBS Ram Prime? 


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About the RCBS Ram Priming Unit

I’ve been using the RCBS Ram Priming Unit for some time now. When the priming system on my Lee press broke, I replaced it with this system, which is both affordable and consistent. I’m a big fan of on-press priming as it keeps everything contained. 


The Ram Priming Unit gives reloaders better feel by seating the primer at the top of the press stroke. Reloaders can also preset a positive stop to speed the process. It works with any single-stage or turret press with 7/8-inch-14 threads and an RCBS® type single-stage shell holder. The unit includes large and small primer rod assemblies for Boxer-type rifle and pistol primers.

What’s in the Box

The ram priming body comes with a lock ring, primer rod holder, large and small primer rod assemblies, and written instructions. You will need the appropriate shellholder for your cartridge. 

Priming Methods and Tools

There are a number of priming tools that seat by either feel, hard stop, or both. On-press priming is either built into a press or added with use of the RCBS ram prime. Off-press priming options include bench top tools and hand tools. You can choose to prime by feel or by hard stop with the ram prime, whether you focus on the leverage of the press or end on the press with the linkage.

Set-Up and Use

The first step is to put together the large and small primer rod assemblies. Each has a plunger, spring, sleeve, and rod. Slide the sleeve over the plunger and put the spring behind it.

Thread this combination into one of the rods, it doesn’t matter which one, until it bottoms out. A small hole in the rod allows you to use a small punch or paperclip to further secure the assembly.

Repeat the process for the remaining primer size. I set up an RCBS turret press with Ultramount on the Ultimate Reloader Bench System, and slid in the primer rod assembly where the shellholder typically goes.

Priming new 6mm Creedmoor Lapua brass, I inserted the small priming rod assembly and snapped the appropriate shellholder into the die body.

Next, I brought the lock ring up to the edge of the threads, raised the ram, and began threading in the ram prime, stopping when half an inch of the die protruded above the press. When I was content with its position, I hand-tightened the lock ring. (It doesn’t have a set screw.)

While everyone has their own tricks, I like to spread out my primers on a primer tray for easy access, anvil up. To prime by feel, I placed a Federal small rifle primer into the primer rod assembly with the ram raised.

I then lowered the ram, placed a case in the die body, and ran the ram up again, feeling for a consistent seat. (Be careful not to crush primers as you have considerable leverage.)

To prime by hard stop, raise the ram and back the die body out until the threads are almost flush. Secure the lock ring and position the shellholder towards you for easier priming. From here, place a primer in the primer rod assembly, and lower the ram. This seating method will take some trial and error. I ran the ram up into the case, but immediately realized the case was stuck, indicating the die body was out too far.

Proud Primer

I screwed down the die body until cases easily slid in and out with flush primers. I prefer this method as it’s especially consistent and I don’t have to think about the process as much as I do when seating by feel.

Properly-Seated Primer


The RCBS Ram Priming Unit is a great alternative to hand priming and allows you to prime on any press without a built-in priming system. It offers considerable leverage for stubborn primers, saves space on the bench and is affordable, making it an ideal backup priming solution.

Get the Gear

Order the RCBS Ram Priming Unit from RCBS or Midsouth Shooters Supply

RCBS Turret Press at RCBS and Midsouth Shooters Supply

Lapua 6mm Creedmoor Cases

Federal Small Rifle Primers at Midsouth Shooters Supply

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Kyle Shields

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