I read where the Marines were picking off Germans at 800 yards. The Germans didn’t realize that that was normal for our Marines. They were trained to shoot at least that far.
If you go back to the beginning marines serving on ships were riflemen who in battle focused on shooting enemy seamen on the opposing ship, including the riggers whose loss would hinder the vessel's ability to maneuver. Such shots were difficult if you take into account the rifleman is firing from a deck that is moving forward and simultaneously rolling while his target is also in motion.