Talking about tipping points, this may been the event got us started down the road to the overbearing security presence that now accompanies any kind of public appearance by a government official. 40 years ago a certified nut-case tried to kidnap Princess Anne. He failed in his attempt and was apprehended at the scene, but before officer Edmonds tackled him he had shot four of the eight people who were trying to protect the Princess.
All four of the people shot recovered. I don't know whether this is a testament to the skill of the British surgeons or the pop-gun size caliber of the weapon. Probably a combination of both. I couldn't find any information about the weapon.