Up where I work in Maine it is very unlikely to get a 1000 yard shot.600 to 700 yards would be max.If I can get it shooting good at 500 meters I'll not be afraid to use it up there.I have never thought of a 338 Win Mag as a 1000 yard gun.Has anyone tried it out that far?When running the ballistics of this bullet at 2400fps it looks to have enough energy on elk sized game to 1000 yards at sea level (1465ft/lbs). However, one needs to look at impact velocity as well so that the bullet still has enough speed to open and come apart. I doubt you would want to drop below 1650-1700 fps impact velocity which would put you around 750-800 yards. Maybe someone will chime in with experience on minimum impact velocity with the 300 OTM.