In 9mm the shellplate doesn't always work, certain brands get "hung" by the extractor groove.It is because of the differences from mfg to mfg. I use the #10 plate for those. When you have the cases in the slot, you can look under it to see if there is any space between the casehead and the ram baseplate. I haven't seen that in .40 though. The plates are hardend, otherwise I was going to take my #8(9mm/.38) to work and machine a few thou bigger opening so it would work better.
I would be interested if your .40 cal is actually doing that.
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