In trimming hulls for my 2" 12 gauges, I prefer using a Harbor Freight 2" chop saw and a plastic jig an Ebay seller made. The jig is clamped in the saw's vise. The jig has a groove in which sits the shell's head's rim. The drop of the saw precisely cuts the hull which is rotated by turning the head a few degrees as the blade drops partially through the hull. The hull is precisely trimmed in a few seconds. The Ebayer offered 2.5" jigs, too. Gil
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