I use the RCBS automatic priming tool. It's fast and works but its not consistant enough for my liking. I try my hardest to put the same amount of pressure on the handle when I prime each case. But it clearly doesn't work out as I plan. I can tell just by looking at the primers depth that they don't all seat the same. And I can even feel the difference when I go over the primer with my thumb. So for best accuracy I want something that seats them securely in the pocket, all at the same depth!