Whichever way you slice it Nevill left the person with the gun in the main bedroom with his wife. You don't know why and neither do I. Perhaps he made to disarm that person and got shot four times in return. Do you think he would have kept on going in the face of that regardless of who was holding the gun? It was the gun stopping him, not the size or sex of the person holding it, surely? He probably did go to find a weapon, but he didn't mamage it.
Jeremy had probably already shot June dead at that stage, or so he thought, and as the last four bullets didn’t kill Nevill that rendered Jeremy unarmed.
So that’s THAT theory of yours blown out the water, because if Jeremy had more bullets in the gun he’d have fired even more into Nevill as he raced down the stairs...
You also seem to think Nevill couldn’t have disarmed Sheila, but that too is ridiculous
Nevill was huge in comparison to Sheila, and the gun was so long — which means he’d have easily been able to disarm her by simply heaving it away and out of her grasp
She was as weak as a kitten; found it hard to focus; was unable to even stir coffee without spilling it — and more crucially, had absolutely no experience of using that rifle which Nevill had bought just months previously. In fact, Sheila had no experience of guns at all. So your argument is of no value whatsoever