There is no prettier sound than Quad .50s fired from the back of a 6X6. Prior to the late 50's and the enactment of the Reserve Forces Act, a person could join the National Guard and not have to serve 6 months active duty to attend Basic Training and get MOS trained. It was all learned by OJT thru the unit they joined. There were some fine soldiers thru that program. Sometimes the physicals were cursory and performed at a local Doctors' office. One famous Doctor the Guard used thru the 60s was Leonard Ford MD, who graduated Medical School in 1899. Dr. Ford would ask you a few simple questions. "Ever have any surgery?" "Got all your teeth?" "Can you see the eye chart on the door?" "You can go back to your unit and take your oath."
Getting back to the Quad .50s, the unit had CCKWs with Quad .50s and was firing at passing R-Cat drones at Camp Wellfleet, when this Guardsmans glass eye fell out due to the vibration of the .50s. His physical was by Dr. Ford.
The unit turned in the Quad .50s in exchange for the 75mm Skysweeper Radar controlled AA Guns, the CCKWs were replaced by the 5 Ton M-54 as the Prime Mover. Never learned what happened to the soldier with the glass eye. He probably stayed in, and may have been a WWII Vet. Paperwork was cursory back in the 50s.