If one were to ask a skilled 3 gun competitor the same regarding 6x magnification, with shots ranging from muzzle to 450-500 yards, they'd tell you that 6x is plenty to hit the average target which is 8-12 inches.
All I know is, I have no trouble centering the crosshairs of a 6X on a 12" target at 550 and hitting it. And I'm not what you'd call a highly-skilled marksman.
