On 22/23 April 1918 at Zeebrugge, Belgium, Sergeant Finch was second in command of the pom-poms and Lewis gun in the foretop of HMS Vindictive.

At one period Vindictive was being hit every few seconds, but Sergeant Finch and the officer in command kept up a continuous fire, until two heavy shells made direct hits on the foretop killing or disabling everyone except Sergeant Finch who was, however, severely wounded.

Nevertheless, he remained in his battered and exposed position, harassing the enemy on the Mole until the foretop received another direct hit, putting the remainder of the armament completely out of action.

He appears to have spent most of the Second World War as quarter master, serving as a storekeeper officer (lieutenant) at 104 (Training) RM Brigade, R.M.

On 15 August 1945 he was released from service and in 1964 was made divisional sergeant major of HM Bodyguard of the Yeoman of the Guard.