Before boresighting the night sight, you must boresight the optical
This brings the optical sight's line-of-sight (LOS) into
alinement with the weapon's LOS (aiming point).
collimator can then be used to aline the night sight's LOS with the
optical sight's LOS.
start of each night sight operation.
These operations include when
the night sight is transferred from one weapon system to another,
when operating sights location changes, when the night sight has been
repaired, and whenever the optical sight is boresighted during a
4A in preparation for boresighting the night sight to the optical