Lyman just launched two new bench-priming tools: the Accu-Prime and Accu-Prime Auto-Load. While they have their differences, both feature a unique helical mechanism and can prime both rifle and pistol cases. Let’s check it out!
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About the Lyman Accu-Prime Manual Bench Priming Tool
The Accu-Prime tool comes with priming punches for large and small primers, an Allen key, two mounting screws, and written instructions.
I wasted no time in mounting the Accu-Prime to the Ultimate Reloader Bench System using the two included mounting screws.
(Be sure to check out the 2025 Hodgdon Annual Manual for full instructions on how to build your own!)
I also drilled small holes in the mounting plate to hold the punches and Allen key.
From Lyman:
Lyman’s Accu-Prime™ tool is one of the most accurate and precise priming tools available! What makes this tool so accurate is our patented adjustable priming punch (US Patent #11,713,950). Other priming tools use the top surface of the rim to hold the case during priming, and then either use “feel” for primer depth, or a tool stop of some sort. However, even tools with a stop are susceptible to rim thickness variations, which will then transfer these variations in primer seating depth. Our patented adjustable priming punch is unique in that the primer cup acts as a stop as it contacts the bottom surface of the cartridge case. In this manner, you can precisely control the exact amount of primer depth below the bottom surface of the case.
The Accu-Prime also features a smooth working helix camming system to raise and lower the priming punch, operated by a unique side lever. Primers are placed into the priming cup by hand and then seated using the 90-degree travel side lever. The tool can be positioned for right- or left-hand operation.
Works with all brands of standard shellholders.
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- Top seating accuracy and precision due to our patented primer punch design.
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- Fully controllable and adjustable primer depth.
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- Smooth operating side handle with unique helix camming design.
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- Accepts standard shellholders.
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- Right- or left-hand operation.
This simple system works with standard shell holders. I installed a .223 shellholder from my Lyman MSR die set for testing and dropped the small primer punch into the center.
Now it was time to prime. With this affordable system, each primer has to be placed by hand. Rotate the handle clockwise to seat the primer.
Just like with any other priming tool, you develop a rhythm the more you work with a tool. I found the helical cam extremely ergonomic.
To seat large primers, raise and remove the punch, swap out the shellholder, and add the large primer priming punch.
The priming rods come pre-set from the factory, but are easy to adjust if needed. Use the included 1/16” Allen key to adjust the set screw in the base.
Turning it clockwise increases seating depth while counterclockwise reduces seating depth. One complete revolution will provide a difference of 0.025” in seating depth.
About the Lyman Accu-Prime Auto-Load
The Accu-Prime Auto-Load comes with the main body, large and small primer punches, written instructions, mounting screws, three Allen keys, and two primer tubes (large and small).
Each of these primer tubes have weighted rods and clips.
The Auto-Load base also has integral storage for the primer tubes and punches.
From Lyman:
Lyman’s Accu-Prime™ Auto Load tool, one of the fastest and most accurate priming tools available! What makes this tool so accurate is our patented adjustable priming punch. Other priming tools use the top surface of the rim to hold the case during priming, and then either use “feel” for primer depth, or a tool stop of some sort. However, even tools with a stop are susceptible to rim thickness variations, which will then transfer these variations to primer seating depth. Our patented adjustable priming punch is unique in that it stops against the bottom surface of the cartridge case. In this manner, you can control the exact amount of primer depth below the bottom surface of the case.
Additionally, the Accu-Prime Auto-Load uses a unique linear rail system for the primer feed tubes. This produces an extremely smooth primer feed operation, and consistent primer drop.
The tool is operated by a side handle which activates our slick camming system for easy primer seating.
Works with all brands of standard shellholders.
-
- Top seating accuracy and precision due to our patented primer punch design.
-
- Fully controllable and adjustable primer depth.
-
- Unique linear rail system to operate the primer feed tubes.
-
- Smooth operating side handle with unique camming system.
-
- Accepts standard shellholders.
I mounted this to the Ultimate Reloader Bench System just how I had mounted the base Accu-Prime. Once again, I started with .223, installing the standard shellholder and small punch.
I installed the cotter pin on the primer tube, placed the primers flat-side down, and picked them up one by one with the tube.
Next, I inverted the tube, placed it into the Accu-Prime body, and used the weighted rod to force any primer stuck in the collet down. Working the helix cam deploys and seats a fresh primer. It was smooth and much more convenient to use than the base model.
Swapping to prime 6.5 PRC brass required switching to the appropriate shellholder, large primer punch, and tube.
From here I loaded the primers, installed the tube, dropped the rod, and proceeded with priming.
Conclusion
All primers seated with both the Accu-Prime base model and Auto-Load were below flush and felt good going in. As aforementioned, I am a fan of the hex cam system.
Both of these models come with different features at different price points. They are available directly from Lyman and at select retailers.
Get the Gear
Lyman Accu-Prime Auto-Load Bench Priming Tool – MSRP: $174.95
Lyman Accu-Prime Manual Bench Priming Tool – MSRP: $69.95
Hodgdon Reloading Annual Manual at Midsouth Shooters Supply
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Thanks,
Gavin Gear
