Photos: Basic military trainees learn weapons operations Published Aug. 26, 2022 By Brian Boisvert 502nd Air Base Wing Public Affairs JOINT BASE SAN ANTONIO-LACKLAND, Texas -- Trainees from the 321st Training Squadron learned how to operate the M4 carbine rifle during the second week of Air Force Basic Military Training at Joint Base San Antonio-Lackland Aug. 23. The trainees were taught safety and muzzle discipline, as well as proper positioning and handling of the weapon.