I'm sure you know that the device is supposed to seat the primer a fixed distance below the case head. It does that. There are more than one problem with that design. First, the brass must be uniformed with respect to primer pocket depth. That's doable, but it's also a moving target. Brass flows to the case head as well as flowing to the neck and shoulder. If anyone doubts that, try using a fixed depth primer pocket uniformer until it reaches full depth and then fire the brass 2 or 3 X. Use the uniformer again and you will find that it will remove additional brass that has flowed into the case head. That means that for the PR seater to work as advertised, the primer pockets would have to be uniformed virtually every firing to maintain a consistent depth between individual pieces of brass.
The second issue is that every primer pocket uniformer available today indexes off the case head. The PR (like most, if not all) tool indexes off the forward edge of the case rim. If the rim thickness varies then the distance to the bottom of the primer pocket varies. There is not a commercially available tool to correct that problem if it exists.
That tool looks like a well machined and finished piece, but it won't do anything that a good hand held tool like a 21st Century, K&M or Sinclair will do at 1/4 the price. The bottom line is that the primer anvil needs to sit firmly on the bottom of the pocket and there's a bunch of tools that have worked well enough to win many benchrest championships without the expense. That P.T. Barnum guy comes to mind again.
Thanks for yor constructive reply. I'm going to take a look at all the alternatives you mention here.
