Jeffery, the one thing I know about forming 6mm and 7mm TCU brass is that I have to leave them long for fire-forming or they will end up short. Kinda makes sense when you think about it. (Thinking specifically about the Roberts forming) I am very curious about the 7X57 powder puff loads ending up shorter? That just doesn't compute, guess I"ve still got plenty to learn. Thanks for sharing, this is very interesting.