Close quartars combat, works very well in citys and a urban enviroment. Problem is a rifle round will go through several houses, a shotgun round (depending on the round used)will only go through 1 or 2 walls, in acity or urban enviroment you don't need the long range ability of a rifle a shot gun would be just as effective. And a shot gun fires several pellets, making it easier to strike a enemyin a frantic gun fight