I have that same set-up. Recently I tore mine down for cleaning/lube. If you haven't, I'd suggest you try that first. It isn't difficult, and you might find some "crud" in there keeping the mechanism from advancing fully. Primer residue may be a culprit, or granules of powder. I deprime and wet clean my brass before it goes through my machine, but if you don't that may be what's causing the problem. Anyway, that's just my best guess. Good luck, and let us know what you find out, ok? By the way, I've had my SDB since the mid-'90's and it's still going strong. Dillon has been great about keeping it running on the few occasions it needed something.