Most collimators have an alpha-numeric grid that is fixed in a very precise, consistent position relative to the bore of the weapon. The grid pattern itself varies based on the type and magnification of sights used. While the grid can be easily customized to meet the requirements of a specific end-user, we have created three standardized grid patterns that work with most weapons used by US military and law enforcement organizations.
The Small Arms Collimator provides two types of reference points, which we refer to as Common Zero Position (CZP) and Personal Zero Position (PZP). Understanding each of those reference points and how they work is critical to using the collimator effectively. CZP is used before a shooter has established zero to speed up the initial zero process. PZP is used after zero has been established to confirm or return to zero.
I personally love the collimator. I was in charge of a rifle range and used them daily for confirming zeroes when a shooter said they were having issues. At the infantryman level, we used them as a quick reference before, during and after patrolling. Weapons and optics get knocked around a lot on combat patrols and this single item offered the confidence needed when we were worried about returning fire.
The Army's SWEAT model, which was developed by the Maneuver Center of Excellence (MCoE) at Ft. Benning, GA, is useful for understanding combat weapons as a ‘system of systems’- and for understanding the elements involved in establishing and maintaining zero. Within the SWEAT framework, the individual weapon ‘system’ is comprised of: Soldier (or shooter); Weapon; Enhancements (i.e. optics and mounts); Ammunition; and Training..
A large percentage of military and law enforcement personnel are operating with rifles that are not zeroed. The implications of this are enormous. For the military, it means reduced lethality and increased casualty rates for friendly forces and non-combatants. For LEOs, it increases risk to officers and innocent bystanders (and increases liability).
The SAC mandrel (or spigot) is engineered and manufactured very precisely in order to make it rigid and durable AND to protect the barrel. However, shooters should still be careful when inserting the mandrel in order to prevent damage to the SAC or the weapon.
Common Zero Position, or CZP, is located at coordinates 'I, 9' on the collimator grid. It is primarily used to get shooters close or ‘on paper’ prior to live fire zero. CZP can also be used as an emergency zero for shooters who do not have a recorded PZP.
Establishing and recording a Personal Zero Position (PZP) allows shooters to quickly and accurately confirm zero in any environment. PZPs can be recorded for different distances, types of ammo, elevations, sights, etc.
Once PZP has been established and recorded, shooters can quickly and accurately confirm zero any time- as part of pre-combat checks, at the beginning of each shift, etc. This ensures that shooters always go into the fight with a properly zeroed rifle.
The collimator is designed to be used in all light conditions. To use it during low light conditions, or with an image intensified night vision sight, an included LED Illumination Module is used to backlight the collimator grid.
Each collimator comes with a confidence gauge that is used to ensure that the collimator remains accurately calibrated. It can be used at routine intervals (i.e. one time annually) or any time the collimator is dropped, bumped, etc.
Collimators are calibrated to a specific zero distance to make the initial zero process as fast and easy as possible. This setting only matters when establishing CZP, though. It does not affect Personal Zero Position. And, if you want to establish zero at a different distance, you simply adjust point of aim on the grid.