Yeah that is a little odd that the night sight goes out that far, but it may be there for cases where you have other illumination (flares, fire, etc) or maybe low light, but not totally dark conditions.
You can also fire at muzzle flashes way in the distance, though I've only done that with HE at night against recoiless rifles/infantry.
Edited by Ryujin (04/24/12 09:11 AM)