MIL-STD-1913, MILITARY STANDARD: DIMENSIONING OF ACCESSORY MOUNTING RAIL FOR SMALL ARMS WEAPONS (03 FEB 1995)., This document establishes standard methods of dimensioning accessory mounting rails for small arms weapon systems. It also establishes uniform accessory mounting rails And requirements that are interchangeable among the different units of the Defense Department. Adherence to this standard is mandatory in the preparation of drawings, specifications or technical data packages for the accessory mounting rail used for small arms weapons.