Just my two cents..... Excellent questions asked by Ramblin_Razorback and an excellent answer by Mule Deer.
I don't have a 7x57 but I do have a new .280 Rem, that I haven't tried working up handloads for yet, and this gives me some good ideas for my .280 Rem. (I'm talking about what bullet weights and types to try out; not about using 7x57 powder charges in my .280 Rem.)
Thanks for the posts!
Cheers!
-Bob F.