ct kid: been playing around with the STI sabots this summer and i had the same trouble with the roll crimp. I'm using a small drill press @ 600 rpm-a bit too fast- and chewing up the plastic at the edge of the crimp. tried different oils for lube, no luck; grabbed the bottle of dawn dish soap on a whim and put a couple of drops on a q-tip and applied it to the outside of the hull where it will be crimped and the crimp head, and presto, perfect crimps. as for the uneven crimp, a drill press helps, devise some method to hold the shell vertically in line with the crimp head. also make sure they are all to the same length when crimped. the accuracy and penatration of these slugs is awesome, getting one hole groups at 50 yds. from a rem. 870 with rifled barrel.