I'm a bit of an oddball I have an old rcbs hand primer for when I'm away from the bench I don't use much. At the bench when I'm only priming in lage batches, I run my Lee Auto-prime 2. Now that one I can see why Mr Lee was fearful of a potential primer going off then setting others off. It allows you to adjust seating depth and if you adjust to deep then slam your primer in. I would think it could set a primer off instead of just crush it. Other then that I still feed one at a time on the single stage.