How can anyone contemplate Sheila dashing up and downstairs to reload from the bullets spilled near the phone in the kitchen or from the gun cupboard?
If you are prepared to destroy a whole family, especially with .22 ammunition, you would need to carry as much as possible about your person, either in a pocket or gun-belt pocket, or in another magazine, as once you had started you may well have woken up those still sleeping and would have to carry out the rest of the operation in as little time as possible...., Sheila's nightdress had no pockets, and no live rounds, only spent ones and shell cases were found upstairs.
Photographs of the Eley subsonic hollow-points like those used in the Anschutz 525 can be deceptive.
Although longer at about 25mm., their diameter at just over 5mm. is similar to the run of the mill .22 slug-firing air rifle.
An illustration of similar .22's size and penetrating power at short range is shown in this video...,
http://www.youtube.com/watch?v=IeVMaEXk_Yk A still photograph of their actual size (inset) is shown below, which should display at the right scale whatever monitor resolution you are using.
So although small and "delicate" to look at they can cause severe damage to internal tissues and organs by their mushrooming action.
Would Sheila have had the wherewithal to carry out all this destruction bearing in mind that according to Colin she had never used a gun, and who, to others in the family couldn't make a coffee or beans on toast without spilling any of it?
Even Jeremy Bamber himself admitted in police interview that he had never seen her use a rifle.