Seating primers

[huge29]

I don't see how a primer could rock even if it's not all the way down.

The primer is firmly in place, the rocking to which I was referring is just how the brass rocks when you set it on end instead of being nice and stable as the primer is the only thing touching the counter, no brass touching.
Should you have to work the primer pocket on new brass (Winchester)?

 

[Bullet bumper]

The primer is firmly in place, the rocking to which I was referring is just how the brass rocks when you set it on end instead of being nice and stable as the primer is the only thing touching the counter, no brass touching.
Should you have to work the primer pocket on new brass (Winchester)?

Oh , I see what you are saying now , sorry about that .
Is seems to me that your primer pocket uniformer is not doing the job . It only cuts on it's end so depth should be right and it appears it's not right.