The Small Arms Collimator (SAC) is a precision optical device that allows military or law enforcement shooters to confirm zero and/or re-zero weapons, to a high level of accuracy, without live fire.

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U.S. Air Force Security Forces around the world have begun receiving small arms collimators (SAC) for their M4 and M16 rifles. The SACs will be used to ensure that Air Force personnel going into harms way have properly zeroed weapons at all times, thereby enhancing their safety and operational effectiveness.
The small arms collimator allows warriors to confirm zero on weapons in a few seconds in any environment. Using the SAC maximizes the benefit in terms of accuracy and speed that our weapons and sight options have over enemy systems.
For more information on the SAC:
Check out our new article on the Critical Importance of Accuracy in a Zero Confirmation Device
Go to The Small Arms Collimator article.
Go to SAC Grid and Reference Points article.
Go to Using the SAC for Training/ BRM article.
Go to Using the SAC in the Operational Environment Article.
Go to Collimator vs. Laser Boresight article.
Go to the SAC product page.
Go to the SPA Defense SAC product page for GSA sales.
USAF Fields the SAC
SAC Available on GSA
The Small Arms Collimator
Why Use the SAC?
SAC Grid and Reference Points
Using the SAC for Training/ BRM
Using the SAC in the Operational Environment
The Critical Importance of Accuracy in a Zero Confirmation Device
Collimator vs. Laser Boresight