The sequence of events involved use of the .22 bolt action rifle and 8 or 9 .22 LR Bullets (not purchased, and not belonging to Ralph Bamber), and the shooter targeting June in the main bedroom, directing as many as 5 shots at her. Shooter enters the twins room, and shoots both dead with a single shot apiece, then the shooter and Ralph meet head to head in the region of the top landing and the middle landing of the main stairs, where Sheila fires two rounds at him - at this stage I believe that either the bolt action rifle ran out of bullets, or it jammed, enabling Ralph to scurry off towards the kitchen with a view to alerting Jeremy and the police. There was obviously some delay between Ralph being shot at, and Ralph making his two distress calls, one to Jeremy, the other to the police (3.26am). Ralph has got his bloodied left hand fingers gripping the edge of the kitchen worktop, whilst holding the telephone handset in his uninjured right hand, enabling him to make a very abrupt call to Jeremy, without managing to say much at all during that call, then he had depressed the cradle of the phone and then made his more detailed call to the police (3.26am). This coincided with Jeremy trying to re-establish contact with his father only to be greeted by an engaged tone, this was because at that stage Ralph was on the phone to the police informing them that his daughter has got one of his guns...
Step forward Sheila, wielding the rifle striking Ralph with it because she had no more bullets in it to fire, or the rifles firing mechanism had become jammed, so she bludgeoned Ralph with the wooden stock of the rifle, into near or close unconsciousness...