so let me get this straight you had a 300 win mag that shot in the 3's?!?!? with a lightweight barrel no less? based on the pictures you posted except for the one group it looks to me like the old barrel shot better. I think expecting a 300 mag to shoot at or below .5 moa is a tall order at best. .5 moa is really all the accuracy anyone can use anyway. The rest is just being anal.