...IN A ZERO CONFIRMATION DEVICE.  Boresight devices, which are inherently inaccurate, are considered by some to be ‘good enough’ for zero confirmation in the field.  The logic, which makes perfect sense on the surface, is that a given weapon platform does not require a zero confirmation device that is accurate beyond that platform’s capabilities.  Using this logic the M4, as an example, which is commonly considered to be accurate to about 4 minutes of angle (MOA), would only need a 4 MOA capable device to check zero.  If we consider this logic more carefully, though, its fallacy is quickly exposed.  Adjusting zero based on an inaccurate boresight device degrades the overall accuracy of the weapon system.

In combat, the difference between an enemy that is down and out of the fight versus one who is able to continue to send rounds in your direction is often measured in inches. For this reason, we should constantly strive to improve combat marksmanship. The SAC is a very powerful tool for this purpose.

Our weapon platforms and sight options typically provide a significant advantage over enemy weapons in terms of accuracy and engagement speed. Most of that advantage is lost, though, if our weapons aren’t properly zeroed.

The SAC utilizes an alpha-numeric grid that is fixed in a very precise, consistent position relative to the bore of the weapon. For the M4/ M16, the grid is graduated in large, bold squares and smaller, finer squares. The large squares are 4 mils (equal to approximately 14.4 inches at 100 yards) and the small squares are 2 mils (approximately 7.2 inches at 100 yards).  The SAC provides two types of reference points, CZP and PZP...

In the Training/ Basic Rifle Marksmanship (BRM) environment, the small arms collimator can be used to reduce ammunition costs and range time associated with initial zeroing. It has also been shown to improve marksmanship scores. Additionally, frequent use of the SAC emphasizes the importance of maintaining a good zero on weapons at all times and develops the knowledge and mindset needed to use the SAC in operational units.

The Small Arms Collimator (SAC) is a very powerful tool for maintaining readiness at the individual and small unit level. Used properly, it helps to maximize the benefits (i.e. engagement speed and accuracy) provided by our weapon platforms and various sight options.

The SAC allows shooters to adjust or confirm zero on weapon systems in less than one minute in any environment (i.e. in a vehicle, on an aircraft, on board ship, behind cover on a patrol, in a hidesite, etc.) without compromising position. This improves operational effectiveness by: a) ensuring that shooters always have a good zero on their weapons, and b) allowing shooters to select and use the best sight option for their mission and operating environment.