I have the same issues with the "shell plates dragging". In my case however, it is a result of primers not seating deep enough. I have to double tap the primers in to make sure they seat properly or else a high primer will drag and prohibit proper indexing. I believe this issue is a result of the relatively soft frame casting that the primer seating stem is actuated by. Since this post Is called things I would make better...... I would drill the area under the priming stem, tap it and use a harder metal base that could be adjusted/replaced as necessary.