ngb, Neville said that Shiela has gone berzerk with the one of the guns. this would mean that she was firing it , would'nt you think.? and if they were in different rooms...........
haughton - I see the point you are making. I am not sure that the words attributed by Jeremy to Nevill conveyed the meaning that the weapon had yet been fired, and I believe Jeremy's impression was that it had not been. It is just possible that Nevill was under the mistaken belief that Sheila was responsible for whatever was causing him great concern, whereas it was in fact an intruder. However I do find that situation hard to visualise. Why would he have referred to Sheila without something directly indicating that it was Sheila who was behaving in a manner out of control, specifically involving a firearm? I also suspect that if the firing had started Nevill would not have called Jeremy. He would either have tried to intervene physically to defend his family or would have called the police. Calling Jeremy indicates to me that the situation, although difficult, had not become completely out of control and Nevill wanted to deal with it within the family.
I accept of course that I may be wrong on this and what you suggest is a theoretical possibility, albeit one I personally consider unlikely.