Can you shoot a gun in Chicago? Not really, other than old saying of, “It’s better to be judged than carried.” But leave such legalities to gun lobbyists and your elected representatives. An interesting topic is to discuss where and under what conditions a gun can actually be fired, and what might happen according to the laws of science and physics.
First, don’t try these experiments but understand how the people who set them up put in the time and money to safely determine how a bullet reacts in water. Mythbusters had an episode to determine if, like some movies portray, diving underwater protects you from gunfire. What they found was that about eight feet of water is enough to prevent injury. That was shooting directly into the water, firing from an angled position could also change the bullet’s track, making it impossible to aim.
Another experiment was conducted by Andreas Wahl, who fired a gun which was actually submerged. The bullet made it about two meters, roughly the same as what the Mythbusters Crew had found. The fact is that modern bullets are waterproof. When the firing pin strikes there is enough oxygen inside the round to ignite the gunpowder. However, the water is simply too dense for the bullet to travel efficiently through it.
On an Airplane
A common misconception is that shooting a gun in an airplane would penetrate the skin and cause the cabin to depressurize. Actually, the pressurization system would be capable of pumping more air in and maintaining pressure, unless a window were hit, then there would be serious consequences. What you might overlook is hitting a fuel tank, which probably wouldn’t explode immediately but would definitely be a fire hazard, and the plane would be losing fuel at an exaggerated rate. Even worse, is if you hit wiring or a control panel the plane is going down. So if you ever have to shoot while on a plane, make absolutely certain to hit the terrorist instead of something that might be important!
Although guns in outer space sounds ridiculous now, with the rate of space exploration and potential off-world resource mining it might come up sometime in the not too distant future.
Although it has never been tried, scientists can declare fairly accurately what would happen. First, contrary to popular belief, the gun would fire. The modern bullet has its own oxidizer and doesn’t need atmosphere to fire. The bullet would never stop due to inertia, and would actually increase in speed over time as the universe is expanding until it either hits a solid object or nears something with enough mass to put gravitational forces on the bullet. From a different perspective, if not anchored to something large enough to counter the effect, the recoil would knock you back at a rate of several centimeters per second, and because of inertia in a vacuum, your movement would never stop either.
~ Ready to Fire News