Great piece on the societal and cinematic origins of holding your gun sideways. Among others:
During the first half of the 20th century, soldiers used the side grip for the express purpose of endangering throngs of people. Some automatic weapons from this era—like the Mauser C96 or the grease gun—fired so quickly or with such dramatic recoil that soldiers found it impossible to aim anything but the first shot. Soldiers began tilting the weapons, so that the recoil sent the gun reeling in a horizontal rather than vertical arc, enabling them to spray bullets into an onrushing enemy battalion instead of over their heads.
(via tmn)
