Primal Rights CPS_ Lite Evaluation

hm1996

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Staff member

When I loaded for HP Rifle competition, I tried all the tricks to squeeze the last drop of accuracy from my loads and target rifles. Case prep included case neck turning, flash hole and primer pocket uniforming & using lee hand priming tool.

I decided the benefit of all this case prep was greatest at long range, so I took the easy route and dropped all but the hand priming after I quit shooting competition. Accuracy didn’t seem to suffer noticeably at normal hunting distances (out to 300, maybe 350).

I watched the excellent set-up video before receiving the CPS, and realized that my old Herters press might not be conducive to ease of operation w/the CPS as the ram is up at rest with the handle down; exactly opposite of most newer presses. A full 170* stroke is required for full ram travel instead of the 45* of most modern presses. As it turned out, other than setting up backwards to instructions, operation was smooth as silk....more on that later.

I made good use of the time, while awaiting delivery of the CPS by running 350 Win 308 cases through the sizing die to straighten up any dented necks, then trimmed* and chamfered necks. *Trimming, while not necessary, did take a very light cut on probably 50% of the cases.

Measured the primer pockets in 10 or 12 new Win. 308 cases and found they varied .004” in depth (.127-.130”). This was not an issue with the Lee hand priming tool I have been using, as primers were seated by “feel”, but with the much greater leverage with the CPS in a press, I decided to uniform the primer pockets to take full advantage of the precise seating possible w/the mechanical stop of the CPS.

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Guess I was a bit optimistic, as my arthritis cut the primer pocket uniforming short @ 150 rounds. Will have to finish up the rest later.

Next, two primers were seated “by feel”, using the old Lee hand tool to be used as “seating gauges” in setting up the CPS, as suggested in the video. Hand seating resulted in primer depth of .005” below case head.

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The tool arrived this evening and setup was a snap, thanks to the video. This is where I strayed from the video by angling the primer arm slightly to my left, since Herters handle is centered and handle has to be held (up) off the stop to keep ram off of the CPS priming stem; otherwise the priming pin will not drop out of the way to allow priming arm to slide to pick up a new primer.

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The tool functioned flawlessly allowing me to prime 150 cases in just over 19 minutes.

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Out of curiosity, I switched over and primed a couple of 243 WSSM cases to see if any adjustment would be necessary. All that was required was to change shell holder, which took right at 3 minutes.

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Then I switched to some LC 5.56 brass (another 3 minutes to switch) and seated 5 primers. Don't know if I just got lucky or what, but no adjustment was necessary! All primers were .005" below case heads. Thinking I might have just bottomed out, as I didn't measure primer pockets on the 223, I slipped a piece of paper between the primer ram stop and base of die with a primed case in the shell holder and couldn't move the paper.

I'm impressed. Thanks, Orkan and Primal Rights!
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Regards,
hm

 
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Given a night to mull it over, I came up with a modification that (for me) improved the operation of the CPS slightly. Hope this does not void the warranty
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I first tried a Dillon powder measure spring but it was a bit too stiff and I didn't like fastening to the primer tube.

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Then found a whole bag of rubber bands....perfect. Addition of a simple rubber band to return the primer carrier slide to the "prime" position, thus making a simple one way movement to pick up a new primer and assures proper alignment of the primer under case 100 % of the time. One word of caution, follow slide to front w/thumb to prevent slide from slamming forward. (My unit positioned at about 11 o'clock). It also prevents the slide from sliding part way back when not held, due to the slight (15-20*) slant of the top of my press.

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Looking around the loading room for a place to store the CPS when not in use, found an empty RCBS die box that holds complete assembled unit, spare slide, plus shell holders, pins and even the rubber bands.
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Regards,
hm




 
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Well, after close to 1000 cases primed, much to my surprise, I finally found one fault with the CPS-Lite.

Imagine my surprise, when, as I cycled the shuttle to pick up a new primer, the entire shuttle came out in my hand and emptied the tube out on loading bench. (OK, I'll admit to having a few more than 10 primers in the tube
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Not a biggie, but the shuttle stop screw (shiny screw in picture) could use a drop of Locktite to prevent backing out in use.

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I quickly solved that issue with a bit of fingernail polish.

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This small detail certainly does not detract from the utility of the CPS but users might want to put a drop of fingernail polish on their shuttle stop screws.

Regards,
hm
 
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That's odd... that's suppose to have loctite on it! One of my assemblers must have been taking a nap. Sorry you had to deal with that. I know we were a little rushed in trying to get these kits out to you guys to eval... but you still shouldn't have had to deal with that.

Nice innovation with the rubber bands as well. We intentionally left a return to battery feature like that out of the design so that no inadvertent movement (the slamming you reference) could contribute to an accidental primer detonation. However a lot of our users of the full CPS and CPS_Lite do perform that modification.
 
Not a problem at all, orkan. I did have a bit of warning before the shuttle came out had I realized what was happening. The last batch of primers I seated, on the last two or three primers in the tube, I noticed a tendency for the shuttle to bind slightly. All that was required was to jiggle handle a bit and slide would advance so I thought it was just the lack of weight on last primers in the tube and let it go. It was no big deal.

Very smooth operation otherwise. As for the rubber band, I'm always dinkin' around with things to try to improve on them if I can. With my press the rubber band just keeps the shuttle from sliding back about half way when released.

I size and deprime cases, then trim/chamfer after each firing (easier than measuring/sorting after ea firing IMO), using a Lee w/shell holder mounted in cordless drill. Then I have been priming w/either a Lee hand primer or the Dillon press. The CPS meshes nicely with my MO and results in much more uniform seating. Thanks again.

Regards,
hm
 
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