I was the Mining and Gunnery Officer in Abdiel for 12 months a good while after that film was made after the 40/60 Bofer was fitted. I never had any training, they gave me a book with about 100 volumes. I wish I'd seen that film before. Now I know what I was doing! The mines I laid we loaded in Newton Noyes jetty in Milford Haven. Although they were inert (some made of concrete) a lot of the little wizzbangs on the sinkers were hazardous if handled incorrectly and worst of all was the Visual Mine Firing Indicator buoy seen on top of the mines here. They had been known to go off prematurely and were full of phosphorous. Thank god for good NCOs. Don't know where I'd have been without them. Respect to you guys.
Jerry.