I find it fascinating at the very least and unbelieveable at most; that the socos and forensic personnel have not positively specified the actual calibre of all the bullets................as far as they are concerned they are just .22 LR 'although some may be different'.......Total rubbish ballistics and firearms forensics (IMO)
For a bullet to be a .22 it can be anything from .21 (an Armalite, capable of taking someone's head off at 600m yards) through .22 (air rifle calibres can be .22 but 5.5mm or 5.6mm) to .23 (fairground rifles like the Winchester pump) and .24 up to .25..........
Just put '22 rimfire ammo' into a Google Images search to see what is and was available.
If you want to see the law as it was in 2002 (2013 is now available) here is a link:
https://www.gov.uk/government/publications/firearms-law-guidance-to-the-police-2002If a shotgun had been used on any of the victims it would have to have been a solid slug otherwise there would be numerous small pieces of 'shot' (lead balls) in the wound (at close range or all over the room at a greater range).......
Solid slug ammunition is not available in the UK*** as it warrants an FAC; however several enthusiasts load their own as solid slug and are properly FAC registered.
***Certain 'specialists' (Crown Servants) are permitted and it is specially manufactured for their use as are other specialist rounds.
Depending on cartridge size, there could be anything from 100 - 500 pieces of shot in one cartridge (I'm using those figures as a guide because there are many cartridge variations)......
On top of all that, there would have been evidence of a wad (a plastic or fibre packing between the propellant and the load, whether it is shot or solid slug) at close range that could well enter the wound as well.
Furthermore a shotgun discharge is significantly louder than a .22 rifle and it would almost certainly have been heard.........silencers are rare on shotguns and full barrel length moderators tend to be used if the need arises.
I have some cartridges here which are for 12 bore use, 00 buckshot 9 balls per cartridge.....one would probably have removed the best part of SB/C's head if fired immediately under the chin, as would many of the other cartridges.
At the time of the WHF incident, multi-shot shotguns were common and could be semi-auto or pump action, holding up to nine rounds........
Jack