Hi,
Trimming hulls is easy if you have a drill press. I just chuck in a 4" cut off wheel, lock the press at the right height and slide the hulls across the wheel. It slices the hull perfectly. takes about 20 seconds each. I doubt it matters but I do this with plastic 10 gauge Federals and Remingtons and 12 gauge STS. I haven't tried papers but it ought to work as long as the hulls are stiff enough not to dent.
Lawrence