I have had both, my take is:
Good points, 338 Lapua ;
wind drift, retained energy.
Good points 300 Win mag. ;
Trajectory, burns less powder, cheaper components, less recoil, lighter rifle.
Easier to shoot. Plenty of energy at long range. Normal sized action.
Better component availability and selection.
Bad points 300 Mag.;
more wind drift.
600yds no question the 300mag wins, the 338 Lapua advantage doesn't show up until you get further out.
Thanks for your 'personal' experience - knowledge - recommendation.
I've always liked the 300 Win Mag, can't really define why. Red/Blue
Vanilla/Chocolate
Jerry