Whilst having smoko I thought i'd try another priming tool with the Whire River primers.
It's a 30+ year old RCBS tool the old ones that have the interchangeable posts with the sprung loaded support cup and use the standard clip-in shellholders.
Bugger me dead, it seats these primers without much force where the other one on the table, with the fits-all shellholder, struggles bigtime.
Only drama is you have to single-feed the primers in, but the speed and ease of seating them compared to the newer one makes it actually no slower.
I have another older one at the other place with a primer feed plate, but it's 1-1/2hrs away and stuff that.

- old rcbs priming tool.jpg (686.94 KiB) Viewed 2388 times
So just a heads-up to some who may be reading this and think these primers are difficult to seat, or use, but just check what tool you are using.
Some, with big long handles and grips are designed in the forcing-cam system to be actually p*ss-weak dispite the cost or all the fancy reviews.
The Lee one I have, for example, when trying to seat these primers it feels about to snap in half, where this old style "slow" RCBS tool is a breeze.
Try a few before you judge.