I use the cci empty shotshells, Then using abt a 3/8 drill bit, I drill the end out of an empty plastic shell. then glue it end to end to an undrilled shell, using good ole pvc cement [plumbers glue for pvc pipe] let dry 30 minutes min. fill as normal [except they now hold a 11/16 oz. charge] with #7 1/2. Load over 6.4 gr. of bullseye, in resized primed , but not belled cases. If I take the seater stem out of my seating die, it will hold the shot shell down and apply a slight crimp. All this to make my .44 into a .410!!!! Am currently experimenting w/ a new method.... will update if successful. Good luck and be careful. MV BTW the standard .44 cci shot shells, are effective on squirrels and barn rats, but, the 357/38's are not.. .410 and equivilent are obviously better on rabbits etc...