 After the war, Begg joined the cruiser as operations officer for the destroyers in the Mediterranean Fleet.Promoted to captain on 30 June 1947, he was given command of the gunnery school at Chatham in 1948 and of the destroyer as captain of the 8th destroyer flotilla in August 1950.The "Cossack" took part in the Korean War being involved in the pre-invasion shelling and blockade of Inchon and Begg was mentioned in despatches and appointed to the Distinguished Service Order on 3 October 1952.