Passport, FWIW, H4350 and Nosler solid base 140's (discontinued)or Hornady 139 FB Interlocks. I run WW cases and Fed match primers.
RL19 looks to be good, too, if you have a supply.
EFW:
Not trying to be preachy but as Gaviidae said, to make the 7x57 shine know your chamber and throat. Each rifle is different and comparing two cases of near capacity like the 7-08 and 7x57 with just a couple grains between them comes down to the rifle and careful handloading, IMO, rather than the cartridge.
