Or in real life, the Marine would have holographic contact lenses with a
targeting reticle linked to his weapons, so that crosshairs would appear in
his field of vision, showing him where his rounds would hit.
Thus the crosshairs would simulate... crosshairs.
"How many more, Harry?" said Dumbledore, eyes puddling with tears. "How
many more have to be buried before your thirst for vengeance is satisfied?"