Sergeant McJunkin was a member of Company F, 2nd Battalion, 5th Infantry Regimental Combat Team. He was seriously wounded by the enemy in North Korea on 14 October 1951 and returned to duty on 16 October 1951. He was Killed in Action while fighting the enemy near Yul-Gol, North Korea on 17 January 1952.

McJunkin was awarded the Purple Heart with Oak Leaf Cluster, the Combat Infantryman 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.