On July 18 1944, while taking part in Operation Goodwood (Battle of Normandy), he was commanding a group of M4 Sherman tanks east of Cagny that suddenly encountered a mixed group of four German tanks at a range of only 300 yards (270 m). The group included one of the formidable Tiger II heavy tanks. As he knew his Sherman's gun would have little effect on the Tiger's thick armour, Gorman ordered his driver to ram the German tank. Gorman's gunner had time to fire one round before impact, but the shell was an explosive one, not armour piercing, and had little effect.

Both tanks were disabled by the collision and both crews immediately abandoned their vehicles. The last to leave the Sherman was the assistant driver, whose exit was slowed by his hatch being blocked. Once clear of the tank, he followed a group of men who were running for a nearby ditch, only to discover after joining them that they were the German tank crew. They glared at him, so he simply saluted and ran off to join his own crew.

While his crew took shelter, Gorman ran to fetch a Sherman Firefly, a Sherman fitted with the powerful, British 17-pounder anti-tank gun. One of the Firefly's four crew had been decapitated and two others were in shock, but Gorman was able to remove the body and take command of the tank. With the Firefly, he was able to complete the destruction of both the Tiger II and his disabled Sherman.

John Reginald Gorman (1 February 1923 – 26 May 2014) joined the Irish Guards in 1942, becoming a Lieutenant in the 2nd Battalion of the Guards Armoured Division. Gorman was awarded the Military Cross for his actions, while his driver, Lance-Corporal James Baron, won the Military Medal. Gorman was promoted to the rank of Captain.

Later in the war, Gorman took part in Operation Market Garden. The Irish Guards were a leading part of the ground part of the operation and Gorman's tanks reached the bridge at Nijmegen before the operation was called off.

Photo caption: John Gorman's Sherman tank Ballyragget, and the Tiger II tank of 503rd Heavy Panzer Battalion that it knocked out by ramming, July 1944.