MIL-S-50783 (AMENDMENT 1), MILITARY SPECIFICATION: STEEL ALLOY, SPECIAL PURPOSE FOR AMMUNITION COMPONENTS (HF-1) (05 SEP 1986)., This Amendment forms a part of Military Specification MIL-S-50783(AR), dated 20 September 1973 and is approved for use within the US Army Armament Munitions and Chemical Command and is available for use by all Departments and Agencies of the Department of Defense.