A week later Mr Bell, a surveyor, mentioned his misgivings about the strange man he had met at Callander Rifle Club to a colleague. It was then 9.25am on March 13 and, as Mr Bell was to soon discover, the man he was talking about was preparing to become the mass murderer who claimed the greatest number of victims in British peacetime history.
Recalling the encounter to the Cullen inquiry, Mr Bell said: "I just did not feel comfortable with him. He came across as very intense."
Listening, out of sight in the gallery of the Albert Halls in Stirling, where the inquiry is taking place, were the relatives of the 16 children Hamilton killed.
Mr Bell said that when he arrived at the rifle club, Hamilton was pointed out to him as "the strange man from Stirling with the odd voice". He noticed that Hamilton was firing rapidly, using hundreds of rounds of ammunition, compared with the 10 or 15 rounds he used. "He told me that he had not been shooting for some time but was getting back into it because he needed the practice," Mr Bell said.
Prompted by Crown counsel Ian Bonamy QC, Mr Bell, 29, went on: "I asked him why he needed the practice. I assumed it was for competition, but he said it wasn't - he just needed the practice."
His unease was heightened when Hamilton insisted Mr Bell, a probationary club member, use his more powerful weapon. "He was very persuasive. I did not want to shoot a full-bore pistol. I was quite happy with my .22." Afterwards, Mr Bell reluctantly agreed to give Hamilton a lift back to Dunblane railway station, but became alarmed when he asked to sit on the back seat.
"I was really uncomfortable by this stage at Hamilton being in the back of the car with the firearms, particularly as nobody in the club knew I was giving him a lift."
During the journey, Hamilton became agitated as he explained how the police had confiscated a self-loading rifle following the Hungerford massacre and paid him only Pounds 700 compensation. "He was quite aggrieved at the police having taken it off him," Mr Bell said.
Changing the subject, Mr Bell asked Hamilton about his work as a "gym teacher", but again, "he became quite angry and wondered if I was questioning him."
Mr Bell's dislike of Hamilton was shared by other members of local shooting clubs, who regarded him as a "creep" and a loner, the inquiry heard.
According to Stirling Rifle and Pistol Club secretary Gordon Crawford, Hamilton was, until the weeks leading up to the tragedy, an infrequent member who did not socialise or take part in competitions.
While most enthusiasts took careful aim, Hamilton would "just blast away" at the target, emptying all 12 rounds in 20 seconds and without bothering to reload as competition rules required. Mr Crawford said: "I tried to give him instruction but he was not open to that advice." Hamilton had been "inherited" from another club which had folded, and although members were unhappy that he did not enter into the spirit of the sport, officials were reluctant to expel him for fear of being sued.
On his last outing with the club on March 2, Hamilton again drew attention to himself by sticking orange markers on the head and chest of the human-shaped targets. Mr Crawford said: "I told him, 'That's not what we are here for' and took them off." On the command to open fire, Hamilton, who was using the Browning pistol used in the massacre, again fired off all 12 rounds immediately.
William Campbell, the club's competitions secretary who gave Hamilton a lift home after the March 2 meeting, recalled: "He stroked his guns and talked about them as if they were babies, as if that was what he lived for."
But while the shooting club tolerated Hamilton's strange ways, the Scouts Association held him in deep suspicion. Hamilton had been sacked as an assistant scout leader in 1974, but had since set up his own unofficial youth group.
Brian Fairgrieve, Stirlingshire county commissioner for the Scout Association, told the inquiry Hamilton had been dismissed following two badly organised expeditions to Aviemore during which boys aged 10 and 11 were forced to sleep on the floor of his van in freezing temperatures. However, Mr Fairgrieve, a retired general surgeon, admitted that he also suspected Hamilton of paedophile tendencies. He had no evidence, but relied on "clinical acumen".
"He gave me more and more cause for concern because I did not think he was particularly stable. I formed the impression he had a persecution complex, had delusions of grandeur and I felt that his actions were almost paranoiac. " Mr Fairgrieve wrote to the Scottish scout headquarters about Hamilton, and he was entered on a blacklist. Hamilton continued to protest his innocence, and accused the movement of blackening his name.
Another scout official, Comrie Deuchars, a sometime neighbour of Hamilton's in Stirling, recounted that Hamilton kept his living-room curtains closed but once, when they were left open, he noticed several pictures of children on the walls.
Mr Deuchars last saw Hamilton on the morning of March 13 as he scraped ice from his van windscreen. "He did not strike me as unusual. The only thing that made me wonder was that he was up at that time in the morning. He was not an early riser."