Not something you hear of too often but the guys in Coastal Artillery still did their service and deserve greater recognition. Would have been long hours of nothing with the occasional alert that amounted to nothing and, perhaps rarer still, action of some sort. A lot of batteries, such as the ones on Rottnest Island about 35 kms from where I sit would have only fired in exercises.
Oliver Hill Battery, Rottnest Island, Western Australia during WW2 Olivers Hill Battery, Rottnest Island, WA Profile