My 7x57 is a WW featherweight with a custom barrel. The factory barrel simply copper fouled more than it was worth to clean it.
While the custom barrel rarely fouls and cleans up within 30 min.
It shoots everything from 120-gr to 160-gr bullets extremely accurate with it's 1:10 twist. It's favorite load is a 150-gr
TSX bullet on top of a healthy load of H4831 to produce sub-MOA
accuracy. But it also shoots other bullets very well.