Quote Originally Posted by Thegreg View Post
I'm using the primer attachment on my RCBS Rockchucker. I know people rate the hand held ones but you get far more leverage on the press, they are consistently seating to the bottom of the pocket, I've no doubt.
I personally think the above is your problem. I have a Rockchucker but shelved the idea long ago of using the press to prime cases - you don't need that extra leverage to seat primers - seating primers is all about 'feel' especially after a few firings when primer pockets become loose and decisions have to be made to bin the brass. If a primer is seated correctly you should be able to see with the naked eye that the primer is below the level of the head stamp - my prognosis is that your press is not seating the primer deep enough.

For your benefit, I took a CCI small rifle primer (CCI 400) and measured its depth with my Mitutoya gauge and it was .121" I then took my RCBS priming tool and seated that primer into a brand new 223 Lapua case, then with a universal deprimer carefully removed the primer and remeasured its depth - now .1165". Seating the primer correctly has the effect of expanding the primer outwards to ensure a good seal in the primer pocket. Perhaps you should try that with your press method.

Maybe you have some one in your area that reloads and uses a handheld primer tool that you can use.