When I had the Rem Classic in 7x57 I tried Federal, remington and Winchester.
None of them were noteworthy. The problem being that they were loaded to safe specs for the older single shots and milsurps.
I ended up shooting the stuff off just to get he brass to reload. Found out though, there was a dramatic difference in case capacity with the different manufactureres. I found a limited supply of old Imperial brass that was great, it had plenty of capacity and was good to work with.
The load I used for hunting drove a 140 gr sierra spitzer at nearly 2900 fps...The 280 remington I had used prior to this acheived nearly 3100 fps with the same bullet...not a lot of difference.
The 7x57 is an excellent round.
Cheers