I have to admit, while watching all the coverage of the Libyan chaos and the rebels firing their guns in celebration, there's one question that kept creeping up in my mind: What happens to all those bullets? Could the trigger-happy rebels actually be hurting (or even killing) people by firing off their guns all willy-nilly? Luckily, Business Insider was wondering the same thing, and it has an answer. In short, yes.
First, an example of the chaos. Here's a clip from CNN that we brought you yesterday, in which there is so much errant and "celebratory" gunfire that the reporter is actually hit with bullet casings:
Now, here's how the popular Discovery Channel show Mythbusters explains the danger:
In the case of a bullet fired at a precisely vertical angle (something extremely difficult for a human being to duplicate), the bullet would tumble, lose its spin, and fall at a much slower speed due to terminal velocity and is therefore rendered less than lethal on impact. However, if a bullet is fired upward at a non-vertical angle (a far more probable possibility), it will maintain its spin and will reach a high enough speed to be lethal on impact. Because of this potentiality, firing a gun into the air is illegal in most states, and even in the states that it is legal, it is not recommended by the police. Also the MythBusters were able to identify two people who had been injured by falling bullets, one of them fatally injured. To date, this is the only myth to receive all three ratings at the same time.
A bullet from a Kalashnikov rifle weighs only about 5 g but leaves the rifle traveling at over 1,500 mph — twice the speed of sound. This gives the tiny bullet the same amount of energy as a brick dropped from the top of St. Paul’s Cathedral, so no wonder bullets tend to kill people.
If there were no atmosphere a bullet fired up into the air would come back down with this same amount of energy, and patently lethal consequences. However, air resistance makes a big difference and cuts the final speed of the descending bullet to around ten percent of the muzzle velocity, or 150 mph, and its energy is the equivalent to a brick being dropped on your head from the height of four feet or so.
Experiments conducted with real falling bullets have confirmed that this is enough to cause significant injury and there is anecdotal evidence that they may be lethal. The victims are unlikely to be those doing the firing, however. Traveling thousands of feet in the air, the bullets are usually caught by the wind and land as much as a quarter of a mile away from the gun-toting loons who fire them.
Howstuffworks.com confirms that such bullets can be lethal, but states the obvious -- the danger is increased in urban areas because of increased population density.
So how plausible is it that someone is actually killed by the practice in the United States? Consider that a 4-year-old Atlanta boy was apparently killed by a bullet fired into the air in January 2010.