I had never thought of them as pellet marks.
Anyway, still no trace of JB transferring other adults' blood in the crime scene.
The mark on the underside of the Aga surround could be where a pellet lodged and it could have been this that AE pointed out to the police, strengthening their thoughts that they were being misled. It is also possible that they moved NB to search for pellets and not just to retrieve the fire debris.
Having possibly found one pellet AE would certainly have carried out a more thorough search given her inquisitive nature and she may have found more. No wonder the police may have brought in a metal detector and did a clean up in the first couple of days. Their kindness may have had an ulterior motive.
It seems a strange place to have a tiny round depression on the underside of the Aga surround.
They probably would not have thought to use the MD on the underside of the Aga surround.
Any chance of a clearer picture? Does BR have any more he can enlarge?