My one moose fell to a .450 Marlin and 325 grain flex tip, so it isn't much of a comparison to what you're asking...but doubt you could go wrong with the 7x57 (or .270 Win) with any decent bullet. I'd pick a partition, accubond, interbond, etc., but even cheaper C&C bullets should work just fine. I'd avoid Sierra, but I am sure one would work with the slower speeds the 7x57 operates at.
Avoid varmint bullets and FMJs and you'll be fine.
