If you're waiting then you're in the wrong spot. I'm a try hard, so I don't snipe much but when I do I know exactly where to be to rack up kills. Oh and any boredom should be erased by the satisfaction of drilling that enemy in the head from 500 yards away.
Try dif tactics. You don't have to at a long distance, look for close cover, brush, shaded areas, windows, and you can be a big help throwin motion mines in heavy fight areas. Use the mortar attack, c4, and try other weapons when in close combat (within
houses/buildings). In short, mix it up. And if your just lookin to take heads off, practice, patience, and more patience!