Both of my Ruger 77 MK2s in 7 x 57 have never been good grouping rifles. This is contrary to most of my other Rugers I have owned.

The first ones magical formula finally was 40 grains of 3031 and a 175 grain Remington SP.
Went from 3 to 4 inch groups with everything, done to one hole at 100 yds with that load. ( Go figure)

The second one, has finally revealed its favorite recipe to me. It was 140 grain Rem SP, with 40 grains of W 748. Once again groups went from 3 to 5 inch groups at 100 yds, ( always a flyer) down to groups you could cover with a quarter with the W 748 at 40 grains. Considering this was done with a Tasco 2 x 7 scope set on 4x, I thought that the rifle did pretty well for itself.

The load has not been chronographed and the bullet was seated to the cannelure, not to the lands. These two Rugers don't seem to care for that practice.

Try this if you have a 77 Mk 2 that is also a fussy eater like these two are.

Seafire Have you tried W760 or H414.I've found them to deliver the best accuracy and top velocity in several 7x57s with 139-145 gr bullets

Snow, I have tried the H 414, but I throttle my velocity down in mine to about 2500 fps. That is why I use the W 748 instead.

If I need more horsepower, I have the 270, and the '06s.