I have a question regarding rules of post-war peronnel using their rank as title in civilian life. Is there a level of rank that one can and a cannot use? My reason for asking is because my Great Uncle who was the Technical Director of a famous Dublin gunsmiths used his WW2 Capt rank on headed paper and correspondance. I find this particularly unusual. I am assuming as he was dealing with Colonels and Majors and foreign ambassadors on a daily basis he used his rank to impress, but I am not sure this was the proper code of conduct. My great uncle was a ballistic expert and wrote a book on the subject before he died in 1964. He was well known in Irish Sporting Circles particularly hunting. I have atached a 1953 newspaper article about him which may be of interest to any rifle enthuasts amongst us, but to demonstrate his use of this title.