It's simple. Between 1969 and the reported 'cessation of hostilities' between PIRA and the Crown Forces, not ONE legally-owned handgun was used in the commission of ANY crime. All the murder and mayhem and killings that took place were all carried out with illegal firearms, or firearms that had been acquired from dead members of the security forces, like the Browning GP35 taken from the bodies of two off-duty RUC officers out fishing when they were murdered, or the two soldiers who got lost and were beaten and publicly shot to death. Both those pistols were subsequently used in crime, but they were not previously owned by shooting members of the public.
When the Westminster government introduced the two stages of the cartridge-firing handgun ban back in '97 and '98, the Northern Irish legislative assembly told them that they were NOT going to institute a similar ban, as there was no record of the criminal use of legally-owned handguns by their owners since around 1926 or so.
The rest of the UK - mainland GB, either has BP or long-barrelled handguns, or pays the price of ownership without custody of their pistol. Section 5 permits you to own a handgun of historical or technical interest, but it must be stored at one of a handful of location - only in England - and if you want to shoot it, you must do so under supervision.
Having spent thirty-three years in the Army, there is no way on earth that I am going to 'visit' my handgun and shoot it while some spotty civilian oik supervises ME to ensure that I'm complying with the rules.
tac