Come on Toad, don't be so naive.
No one collected any guns after the stricter gun laws came into effect, any registered gun owners would have had to surrender them, but for the most the Police held an amnesty asking people to volunteer them. Anyone caught having an illegal firearm would face prosecution (creating another firearm incident no doubt!).
And it isn't a gun ban, more like a ban on certain calibres so there's still going to be guns around. However, I do believe that the stricter gun laws have worked, I'm sure the 'incidents' figure would be 50 times higher than the one reported if not for a gun calibre ban which I can accept. No one in the UK needs .44 magnums, 7.62mm Kalashnikovs, Uzi 9mm's, etc., simply because there is no where to use them. People that enjoy shooting either go clay pigeon, game shooting, target shooting (small bore) etc. Like any law, they are there to be followed or broken. Take road speeding, there are speed limits which are law, they get broken but at the same time they do slow people down as well. I guess it's a compromise of all hell bent abuse and people working within the law (or along the fringe of it - e.g. I break speed limits on occasion on quiet roads but in built up areas I respect speed limits).