During the Korean War , he was an artillery operations specialist in the all - black 503rd Field Artillery Battalion in the 2nd Infantry Division , equipped with the 155 mm Howitzer M1 .
Rangel then enlisted in the United States Army , and served from 1948 to 1952 .
During the Korean War , Rangel was an Rangel     in the all - black 503rd Field Artillery Battalion in the 2nd Infantry Division , equipped with the 155 mm Howitzer M1 .
Rangel then enlisted in the United States Army , and served from 1948 to 1952 .