That's why progressive reloaders make me nervous. Twice I have had .38 spl target loads jam during fast double action shooting, fired only by primer power. Both loaded on progressive machines, one by me, one by a friend. What scares me is if a powder charge is somehow missing, then its just as likely there could be a double charge, right?
When I load now, I watch each case to make sure it has been properly charged. Its pretty easy to see if one is noticeably short or over. I prefear a single stage for most of my reloading, placing all charged cases in loading blocks for inspection prior to seating the bullet.
Larry