I bet when used properly, most priming tools have little impact on accuracy.
I think the differences between priming tools lies in convenience, ease of use, and time savings.
Yup. Tolerances, leverage, ergonomics, seating depth adjustment, etc.
It's not about just seating the primer, it's about getting exactly the same crush/preload on each one for consistent ignition and best accuracy. The same thing can be said about seating dies, but most everyone can agree that the ones with a sliding sleeve produce the most concentric ammo.
I had read once that getting the same preload made a difference, and the only way I could get that was to sort cases by rim thickness, primers by height, and adjust the shims on my Sinclair tool to get the same amount of .003 with a set of depth mics. A real set of depth mics. Not that junk on the end of a calipers lol. I fired 2 10 shot groups alternating each shot on 2 targets and the uniformed group was almost half the size of the other seated with a LEE. It worked, but was tedious beyond anything I wanted to keep doing. Readjusting the shims in the tool for each different size primer wasn't a good solution.
The K&M tool compensates for all of the variables and allows you to make them all have the amount of pre load you wish, which is important to me.
At $147.00, it's not for everyone unless you really need it, or just want it. If someone isn't shooting over windflags, they would be wasting their time and money.
