I loaded 200 rounds of 223 on the 550 today. I took my Lee dies out of the classic turret. I am using cases that have already been cleaned, sized, trimmed, chamfered and the primer pockets swagged. I left the sizing die out. Using the Dillon powder set up. Using the Lee seating die and FCD. The first 100 rounds I had three cases with no primer and one sideways. The second 100 I had one case with no primer. I think most of the priming problems were due to primer pockets not being swagged good. It will take a little getting used to. I found myself a lot of times reaching for a bullet when I should have been advancing the shell plate because I'm so used to the auto index of the classic turret. Overall I am very happy with the press.