Another fact relating to the Joemulvey link you supplied Raggy - your link states that this supposed "artillery duel" took place on Thursday 27th April 1916, and was initiated because Helga fired on Bolands Mill whereupon De Valera raised a Green Flag on an adjacent Tower to misdirect fire from the Helga. Unfortunately Raggy the only time the Helga fired on Bolands Mill was at 20:15 on the evening of the 25th April, now does that register? She did not fire at all on the 27th and after hitting Bolands Mill on the 25th she did not fire on Bolands Mill again. The Sherwood Foresters with the 1 pound hand served and aimed gun from the Helga in 12 shots managed to hit the flagpole at a range of 400 metres - now what diameter was that flag pole Raggy? Bloody small target at 400 metres eh? Especially for a gun on a temporary lash-up of a mounting that is being aimed and fired by someone holding it.

The story told in the link you provided is utter codswallop.