as the title states, is it necessary to size new unprimed brass? i picked up some new IMI 7.62x39 brass a few weeks back at a gun show and now that i got my dies i was going to prime the cases so they'll be ready when i pick up the powder. since i use a hand held primer seater i wondered if i should size them first. quess i'm just being lazy and trying to save a step. would like to hear what thoughts others have on this matter.