Another consideration is the size of shot to be loaded. In my experience, any size larger than #9 bridges in the drop tube, which is not a good thing on a progressive. I have loaded a good many 3" .410 shells, most with #7 1/2 and #8 shot, and I found the best results with a single stage MEC 700 press. I kept a large wooden dowel beside the loader to tap the drop tube when the shot bridged, which was often. I prefer the collet sizer on later MEC presses, but don't own any of them of the single stage variety, so don't know how they would work for 3" shells.
