Corporal Magallanez was a Tank Crewman with the 35th Infantry Regiment, 25th Infantry Division. He was seriously wounded by the enemy in South Korea on 22 September 1950 and returned to duty later that day. He was Killed in Action while fighting the enemy in South Korea on 25 April 1951.

Magallanez was awarded the Purple Heart with Oak Leaf Cluster, the Combat Infantryman's Badge, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.