Jim Davis, Class of 66 posted this:
Date Deceased: 03-21-1969
Age at Death: 21
Cause of Death: explosive charge during enemy attack
City: Columbus State: GA 
Johnston joined the Army from his birth city of Columbus, Georgia, and by March 21, 1969 was serving as a specialist fourth class in Company D, 1st Battalion, 8th Cavalry Regiment, 1st Cavalry Division. On that day, in Tay Ninh Province, Republic of Vietnam, Johnston smothered the blasts of three enemy-thrown explosives with his body, sacrificing his life to protect those around him. Johnston, aged 21 at his death, was buried at the Fort Benning Post Cemetery in Georgia. Medal of Honor Specialist Johnston's official Medal of Honor citation reads: For conspicuous gallantry and intrepidity in action at the risk of his life above and beyond the call of duty. Sp4c. Johnston distinguished himself while serving as a mortarman with Company D, at a fire support base in Tay Ninh Province. Sp4c. Johnston's company was in defensive positions when it came under a devastating rocket and mortar attack. Under cover of the bombardment, enemy sappers broke through the defensive perimeter and began hurling explosive charges into the main defensive bunkers. Sp4c. Johnston and 6 of his comrades had moved from their exposed positions to 1 of the bunkers to continue their fight against the enemy attackers. As they were firing from the bunker, an enemy soldier threw 3 explosive charges into their position. Sensing the danger to his comrades, Sp4c. Johnston, with complete disregard for his safety, hurled himself onto the explosive charges, smothering the detonations with his body and shielding his fellow soldiers from the blast. His heroic action saved the lives of 6 of his comrades. Sp4c. Johnston's concern for his fellow men at the cost of his life were in the highest traditions of the military service and reflect great credit upon himself, his unit, and the U.S. Army.

Follow the link to see his listing on The Wall ~ http://thewall-usa.com/info.asp?recid=26516

 Additional information mirrored in from old BHS website:

 Donald Ray Johnston, Class of '66-Deceased: March 21, 1969

Congressional Medal of Honor posthumously for action in Vietnam. The Medal of Honor is awarded by the President, in the name of the Congress. It is the highest award for valor a soldier can receive.

Here is the official military record:

Johnston, Donald Ray
Rank and organization: Specialist Fourth Class, U.S. Army, Company D, 1st Battalion, 8th Cavalry, 1st Cavalry Division.
Place and date: Tay Ninh Province, Republic of Vietnam, 21 March 1969.
Entered service at: Columbus, Ga.
Born: 19 November 1947, Columbus, Ga.
Citation: For conspicuous gallantry and intrepidity in action at the risk of his life above and beyond the call of duty.

Sp4c. Johnston distinguished himself while serving as a mortarman with Company D, at a fire support base in Tay Ninh Province. Sp4c. Johnston's company was in defensive positions when it came under a devastating rocket and mortar attack. Under cover of the bombardment, enemy sappers broke through the defensive perimeter and began hurling explosive charges into the main defensive bunkers. Sp4c. Johnston and 6 of his comrades had moved from their exposed positions to 1 of the bunkers to continue their fight against the enemy attackers. As they were firing from the bunker, an enemy soldier threw 3 explosive charges into their position. Sensing the danger to his comrades, Sp4c. Johnston, with complete disregard for his safety, hurled himself onto the explosive charges, smothering the detonations with his body and shielding his fellow soldiers from the blast. His heroic action saved the lives of 6 of his comrades. Sp4c. Johnston's concern for his fellow men at the cost of his life were in the highest traditions of the military service and reflect great credit upon himself, his unit, and the U.S. Army.