Are bullets from the air dangerous coming down?
Ok on New Years Eve someone shot a bullet in the air and ended up inside a church during a service.

Can bullets really go through a roof of a house if you shoot it up in the air? Should I be worried?
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answers:
Eisbär say: What goes up must come down... It's all really a matter of physics.

However, although terminal velocity of a bullet can still be very strong, it is not going to have the same velocity, thus impact force that it does when shot straight out at something from a gun, because when a bullet leaves the barrel of a gun, it is under explosive acceleration and has spiral grooves to provide stability and direction to maintain the velocity for the first 3-6 seconds in flight. But eventually air drag and horizontal lag will cause the bullet to lose the stability and force, and fall to the ground.

"A rifle can shoot a 4.20 g bullet at a speed of 965 m/s."

https://hypertextbook.com/facts/2000/Sha...

A bullet shot in the air, will eventually reach a point where it loses all inertia and then it must "fall back to earth." As it falls, it will begin to pick up speed from gravity, but with air friction and drag, it will eventually reach a point of terminal velocity. But what is the terminal velocity of a bullet?

Well, to calculate terminal velocity, you start by multiplying the mass of the object by 2. Then, multiply that number by the acceleration of the object due to gravity and write your answer down. Next, multiply the density of the fluid the object is falling through by the projected area of the object.

Use the terminal velocity formula, v = the square root of ((2*m*g)/(ρ*A*C)). Plug the following values into that formula to solve for v, terminal velocity:
m = mass of the falling object
g = the acceleration due to gravity. On Earth this is approximately 9.8 meters per second.
ρ = the density of the fluid the object is falling through.
A = the projected area of the object. This means the area of the object if you projected it onto a plane that was perpendicular to the direction the object is moving.
C = the drag coefficient. This number depends on the shape of the object. The more streamlined the shape, the lower the coefficient. You can look up some approximate drag coefficients online.

"Of the millions of rounds fired into the sky by trigger-happy celebrants, most land innocently in empty land. Fortunately, the impact of a falling bullet is much less than that of one fired directly at a target. Major General Julian Hatch, a U.S. Army firearms expert, did extensive testing on ballistics and falling projectiles in the 20’s. He calculated that .30 caliber rounds will reach terminal velocities of 300 feet per second (90 m/s) on descent, and determined that, while most bullets will leave a small dent in the ground when they land, that same bullet travelling between 200 to 330 feet per second can still penetrate human skin. The experience of many hospitalized and killed innocents validate his conclusions.

The popular scientists on the TV show, Mythbusters experimented with the premise that “Bullets fired into the air maintain their lethal capability when they eventually fall back down.

They found that a bullet fired straight up (an almost impossible achievement for a human), will tumble on its return trip and falls at a slower rate due to terminal velocity. In addition, they found that a bullet in this circumstance is therefore less lethal on impact. However, they also discovered that a bullet fired at a non-vertical angle will be able to maintain its speed enough to be very destructive on impact. In determining if the myth was ‘Busted’, ‘Plausible’ or ‘Confirmed’, they proposed that this myth would receive all three ratings at the same time."

https://forensicoutreach.com/library/the...

In short, the bullet leaving the barrel of a gun will probably have about 10x's the velocity than one coming down from the sky after being shot straight up into the air, and falling back to earth at terminal velocity:

Based on the above figures, without doing the math, they had come up with (bullet from rifle 965 m/s) v. (90 m/s bullet falling at terminal velocity) so then you can take those figures and do with them what you may.

But as noted, people can be seriously injured by falling bullets. So yea, it's dangerous, if somebody is in the wrong place and the wrong time, and depending on the angle the bullet was shot, and the weather, what type of bullet, where it lands, etc.

This might be better to ask in the Math and Physics section, as you'd probably get some better answers from people better at math, but yea, it's dangerous.
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armouror say: 200 to 330 feet per second any Bullet can Kill
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Bill-M say: Yes they are. There have been reported instance of them killing someone
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say: google it , there are dozens of cases of people getting killed by them .
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hoarseman say: Clearly , it is very dangerous to shoot a gun into the air

However , a bullet which came straight down would be like a pebble being dropped onto your head from a sky scraper , travelling a its terminal velocity -- it would hurt a great deal ,but would be unlikely to kill you , or penetrate .

However ,most bullets are not fired precisely vertically and would not come down totally vertically -- most would have some sidewise velocity --and that's where the real danger lies .
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Ghost Of Christmas Past say: They come down at 400mph. If they land directly on your head, they will kill you. Fortunately, seen from above, very little of the potential target area is taken up by people's heads. If it comes through the roof of a building, it should slow down sufficiently for it not to be fatal.
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Spock (rhp) say: yes, they really can.
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No Chance Without Jesus say: If they have enough punch to go high in the air, then they can reach terminal velocity and be very dangerous
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say: Yes they are absolutely dangerous, that's why you don't fire a gun unless you absolutely have to
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