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he7lius
04-20-2004, 09:20 AM
Can falling bullets from guns fired into the air cause injury or even death??

I see in the news people celebrating stuff by fired into the air but never heard anyone get wounded but the falling bullets.

Does anyone know about anything about this??

jon_s
04-20-2004, 09:27 AM
I have woundered this. I think it depends on the weapon. If the round stays in tact, then what goes up must come down. Perhaps, it would come down slower as gravity is the only thing pulling it down. I know a human falls at 125mph. I also under the impression that a 2p coin droped off a certain famous tower in Paris makes a rather large hole in the ground.

My answer is yes, but it will be going slower than when it left the weapon. I could be wrong though :?

coombsie66
04-20-2004, 09:31 AM
Yeah, im pretty sure a falling bullet could kill, i think if it landed directly on your head it would probably end up sumwhere near you bollox by the time it stopped!

TT
04-20-2004, 09:35 AM
Well, in a world were physics laws would word as they do in theory, no air to slow down the bullet and so on, sure it would be as deadly as a directly shot one... but we have air's friction and so on.. so of course the bullet when will come down will be a little slower.. still deadly IMO..

In the army of course you soon learn to NEVER EVER shot in the air, not even in the desert since your bullet will fall km away and you can have no idea what will be there when it will..

still, I never heard about somebody injuried by a falling bullet I think...

bondw23
04-20-2004, 10:02 AM
apparently they can and do injure/kill people

http://answers.google.com/answers/threadview?id=6638

http://www.kpho.com/Global/story.asp?S=1648055

coombsie66
04-20-2004, 10:15 AM
Well, in a world were physics laws would word as they do in theory, no air to slow down the bullet and so on, sure it would be as deadly as a directly shot one... but we have air's friction and so on.. so of course the bullet when will come down will be a little slower.. still deadly IMO..

In the army of course you soon learn to NEVER EVER shot in the air, not even in the desert since your bullet will fall km away and you can have no idea what will be there when it will..

still, I never heard about somebody injuried by a falling bullet I think...

Even taking into account air resistance, the terminal velocity of a bullet is still going to be very high, due to its high density, and fairly streamlined shape.
I aint standing under one to find out how quick they fall!! :wink:

AlienDB7
04-20-2004, 10:55 AM
Actually I heard a story about someone firing a pistol at the sky and hitting (killing basically) someone few km's away. It was a story featured on TLC in one of their forensic shows, I beleive. Can't remember the detail but I'm sure one of you will manage to find it :)

saadie
04-20-2004, 11:36 AM
yes they do injur and can even kill ........ comeon dude ...

if someone throws a stone at ya ... ur skull can easily crack .....

now bullets have vvv high velocity ....... their results are very devesthating ...

just a piece of advice .......... use common sence before using yer extra ordinar sepcial sence .... :wink:

Chaos in 1983!
04-20-2004, 11:41 AM
indeed they can injure/kill someone...my uncle got a bullet fall down from the sky to the trunk of his car!!..it left a hole just like it was shot directly at it...

possessed_beaver
04-20-2004, 11:47 AM
Can falling bullets from guns fired into the air cause injury or even death??

I see in the news people celebrating stuff by fired into the air but never heard anyone get wounded but the falling bullets.

Does anyone know about anything about this??


yes they can, i read an article, in a believe time magazine after the first gulf war, how people where dying as a result of this very thing, maniley im guessing from the heavy tracer fire, used at the allies aircraft

DeMoN
04-20-2004, 11:58 AM
Late to say that I have heard about falling bullets killing people. Yep it happens, but it is hard for a bullet to exactly land on someone. Its like one drop of rain falling on a penny on the floor.

blah
04-20-2004, 11:59 AM
happens all the time in the US around July 4th.

aliendude012
04-20-2004, 02:24 PM
Think of the old story: dropping a penny off the top of the Empire State building will create a divot 6 inches deep in the concrete sidewalk below. A quarter dropped from the same height will make a crater a foot or so in diameter. Imagine that was your head. You'd die. Now imagine its a bullet, rather than a quarter(same mass, more or less?) and its falling from being shot upward, rather than being dropped from a height(pretty much the same deal). All relative, it'd still kill you if it hits you in the right place.

gigdy
04-20-2004, 07:07 PM
Think of the old story: dropping a penny off the top of the Empire State building will create a divot 6 inches deep in the concrete sidewalk below. A quarter dropped from the same height will make a crater a foot or so in diameter. Imagine that was your head. You'd die. Now imagine its a bullet, rather than a quarter(same mass, more or less?) and its falling from being shot upward, rather than being dropped from a height(pretty much the same deal). All relative, it'd still kill you if it hits you in the right place.

no offense dude but least tru thing ever. Im assuming no one has seen the myth busters show on discovery. they went over the penny myth. they found a penny has a terminal velocity of 62mph. then they shot a penny at that speed at concrete and a skull. it didnt really do any thing to each. though it would cut your head and probably leave a bump. they didnt do anything on a quarter but im pretty sure id doesnt have nearly enough mass.

yes they do injur and can even kill ........ comeon dude ...

if someone throws a stone at ya ... ur skull can easily crack .....

now bullets have vvv high velocity ....... their results are very devesthating ...

just a piece of advice .......... use common sence before using yer extra ordinar sepcial sence ....

what kind of common sense is involved when comparing a rock to a bullet? if you throw a rock at someones head with the same mass as a bullet it wont crack their skull. and bullets have high velocity when they leave the muzzle but it is not nearly as high when falling. Any way its not the velocity of something that kills you its the force

T-Bird
04-20-2004, 08:20 PM
/\/\/\/\/\ I was going to bring up that Myth Busters show too /\/\/\/\/\

geekdiggy
04-20-2004, 08:35 PM
the physics of a ground-to-air-to-ground trajectory go as thus: the bullet contains a certain amount of energy (force or speed, if you will) when it leaves the chamber of a gun. when fired upward, gravity reduces the bullet's energy (force or speed, if you will) exponentially, eventually reaching zero. this zero point is known as the peak of the bullet, the highest altitude it reaches. from there, gravity continues to pull the bullet toward earth, thus INCREASING the bullet's energy (force or speed, if you will) exponentially, until the bullit impacts an object which eventually halts its forward movement. at that point, the effect of gravity on the bullet will have given the bullet enough energy to match the energy it had when it left the chamber of the bullet.

in short, if a bullet is fired into the air and returns to the ground or a grounded target, the energy of the bullet upon contact will be equal to the energy of the bullet upon release.

to put it into perspective, based on the explanations above, the bullet will be traveling at the same speed when it hits the ground or its target as it was when it left the gun.

in other words, if you're on the recieving end of that falling bullet, the effect will be the same getting shot in the face at point blank range

TT
04-20-2004, 08:41 PM
You will also have to consider again:

- air resistance
- the bullet will rotate while slowing down ence at the end of the trajectory probably it won't be pointing the right way -> slower & less penetration power.

geekdiggy
04-20-2004, 08:42 PM
um, trust me dude. science can prove it

TT
04-20-2004, 08:45 PM
Well in your description you consider "the perfect" event.. no rotations and no air resistance and although the bullet a small object, it's still quite important on the final result. I'm not telling the bullet won't be deadly, but not as deadly as if shoot at "normal" range: for sure it won't be pointed the "right way".. or it would be quite rare.

BADMIHAI
04-20-2004, 09:08 PM
You would be right geekdiggy, only if there was no air friction, causing the bullet to reach a terminal velocity. I think the bullet will not do much damage. Let's say you were a towel head (no pun intended)..or just some redneck (like RC :wink: ) and decided to shoot your 7 mm. hunting riffle into the air, on July 4, or because Osama killed some infidels (whichever the case may be). The sectional density of your 7 mm. bullet is .284"
Let's say this is not the hottest July day, so the outside temperature is 300 K, or 27 Celsius. Also considering the density and viscosity of air at 300 K, you get a terminal velocity for your bullet aprox. 35 m/s, which means 126 km/h, or appoximately 78 miles/hour. So if you decided to shoot the bullet straight up, and (let's say) there was no wind, the bullet would land on your head at 78 mph. If you consider the bullet's mass is somewhere around 30 grams, do you really think it would to that much damage? I think the worse it would do is give you a bump.

Sites used:

http://www.processassociates.com/process/separate/termvel.htm ...to find out the terminal velocity of the bullet.

http://www.chuckhawks.com/sd.htm to see the density of a 7 mm hunting bullet.

http://users.wpi.edu/~ierardi/FireTools/air_prop.html

blah
04-20-2004, 10:20 PM
most americans on this site can vouch that atleast once a year, you hear of someone bieng killed or injured from a falling bullet.

BADMIHAI
04-20-2004, 10:27 PM
most americans on this site can vouch that atleast once a year, you hear of someone bieng killed or injured from a falling bullet.


Unless a bullet will penetrate the skin at 78 mph, I don't see how they manage to get injured by falling bullets. Maybe they just say they were hit by falling bullets, when in fact they got hit by stray bullets (ones that have been accidentally shot their way).

SFDMALEX
04-20-2004, 11:39 PM
If a bulit is 25 grams then on landing it will have a much higher weight.

weight=mass x gravity

Although the bullit will have much lower speed it will still be pretty heavy on landing.


geekdiggy- I dont think it would be the same speed. Because in this case we have two situations. A bulit going up. And down. When it is going down the only force helping it pick up speed is gravity. And gravitaional force is much lower then the force that the gun exerts on the bullit.

gravity on earth has the force of 10nm per kg. The force in the gun would have to be double that for your theory to work. and it is much higher then that I think.

but I could be wrong

RC45
04-20-2004, 11:45 PM
http://www.logicsouth.com/~lcoble/dir5/xd.txt


X. Miscellaneous
D. Hatcher's Notebook on Falling Bullets
typed by Norm Johnson ([email protected])
From Hatcher's Notebook:

"Among the many experiments carried out at Miami and Daytona, was this same one of vertical firing. It was desired to find out how fast a bullet returned to earth and how dangerous such a bullet would be if it struck a soldier after dropping from a great height. Many interesting things were learned from this test, and they are given in detail in the "Official Report of Vertical Time Flight for Small Arms Ammunition," in the files of the Ordnance Department. Much of the information given below is from that source.

"At Miami the firing was done from a platform built in the shal- low water of a protected inlet, where water was often calm. A frame was built to hold a machine gun tripod so that the barrel pointed vertically. Instruments were provided to check the angle of the barrel, and the tripod controls permitted any necessary changes in the barrel inclination to be made with ease and preci- sion.

"Out of more than 500 shots fired after adjusting the gun--only four shots hit the platform. One of the shots was a service 30.06, 150 grain flat based bullet, which came down base first...it left a mark about 1/16 inch deep in the soft pine board.

"Two more bullets struck in a pail of water and left only a perceptible dent in the bottom of the pail. One struck the edge of the thwart (seat across a boat, used by an oarsman) in the boat, and left a shallow indent...The last two bullets were 175 grain boat-tailed.

"It was concluded from these tests that the return velocity was about 300 feet per second. With the 150 grain bullet, this corresponds to an energy of 30 foot pounds. Previously, the army had decided that on the average, an energy of 60 foot pounds is required to produce a disabling wound. Thus, service bullets returning from extreme heights cannot be considered lethal by this standard.

"Most .30 caliber bullets seem to attain this final velocity, and it doesn't make any difference how far they fall. Even if a bullet was fired downward from a very high plane, it would still reach the ground at the same velocity. That is because the resistance increases very rapidly with increases in air speed. If the air resists the motion of the bullet a certain amount at 300 feet per second, it will resist three times as much at 600 feet per second and nearly nine times as much at 1000 feet per second.

"A 150 grain bullet weights .021 pounds, and when, in falling, it reaches a velocity where the air resistance balances the weight, the velocity of the fall will no longer increase.

"For a .30 caliber bullet of standard experimental shape, having a pointed nose of two caliber radius, the air resistance on the nose at 2700 fps. would be about 2.3 pounds; at 2000 fps. 1.5 pounds; at 1500 fps. .89 pounds; at 1000 fps. .17 pounds; at 500 fps. .04 pounds; at 350 fps. .025 pounds; at 320 fps. .021 pounds, balancing the weight of the bullet and stopping any further increase in velocity in the case of a falling bullet."



--------------------------------------------------------------------------------
This supports the observations of those who wrote during WW2, that after a heavy battle, a number of bullets were found slight- ly embedded in tar rooftops, all pointed towards the sky.
God Bless!

Norm



http://www.kpho.com/Global/story.asp?S=1648055


By ERIC TALMADGE,
Associated Press Writer

Mon Feb 16, SAMAWAH, Iraq - Eight-year-old Zehra Kadhum was outside near her family's garage playing, when she saw her parents kneel to pray. As she bent down to join them, she felt a sharp pain.


"I thought my sister had kicked me," she said from her hospital bed Sunday. "But I was bleeding and I heard my family shouting and my mother was crying."

Zehra had been hit in the back by a bullet dropping out of the sky.

Like many places throughout Iraq (news - web sites), there is a gun in virtually every household in this desert city, some 230 miles southeast of Baghdad. The sound of weapons — from AK-47 rifles to small-caliber pistols — is as much a part of the evening din as is the chanting of the daily prayers.

Along with offering protection in an unstable country, the guns are a means of self-expression. Men fire off shots to celebrate, to mark funerals or just to beat the monotony of life in the country.

But so many shots are fired that the returning rain of bullets — not stray rounds, but bullets simply falling back to earth — sends an average of one or more people to the hospital each month.

"It's terrible, the governing council in Baghdad has to do something about this situation," said Dr. Ali al Azawi, who removed the bullet from Zehra at Samawah General Hospital last week.

The girl is in stable condition.

"We suffer from this especially here in the south, because everybody has weapons in their house," he said. "It is especially unforgivable at this time, when we lack medicine and health care."

It's easy to get a gun in Samawah.

Ghazi Fahid Wali, who runs one of the many small gun shops here, said he sells from two to four weapons a month, mostly machine guns, but also pistols and old hunting rifles. A Kalishnikov automatic rifle goes for about US$110, he said.

"Among Arabs, we believe that if a person owns a gun nobody will harm him," he said. "Looters will stay away, troublemakers will stay away."

Wali said he had heard of several incidents in which people in town had been injured by falling bullets, most often around especially festive times.

But he wasn't particularly concerned.

"It happens," he said with a shrug.







"Bullets fired into the air can climb as high as two miles before plummeting to the earth at speeds of 300 to 500 feet per second. A speed of 200 feet per second is sufficient to break bone and penetrate the skull, according to a 1995 study by Martin Luther King/Drew Medical Center."

Source: KABC News
http://abclocal.go.com/kabc/news/123002_nw_gun_fire.html <<-deadlink


http://www.straightdope.com/classics/a950414b.html



Datum 3. Still, the question isn't how many people get injured or killed by falling bullets, it's whether such things are possible at all. On further investigation, it appears the 60 foot-pound injury threshold cited by Hatcher may be misleading--a falling bullet's kinetic energy (foot pounds) alone is not a good predictor of the speed it needs to inflict a wound. B. N. Mattoo (Journal of Forensic Sciences, 1984) has proposed an equation relating mass and bullet diameter that seems to do a better job. Experiments on cadavers and such have shown, for example, that a .38 caliber revolver bullet will perforate the skin and lodge in the underlying tissue at 191 feet per second and that triple-ought buckshot will do so at 213 feet per second.

Mattoo's equation predicts that Hatcher's .30 caliber bullet, which has a small diameter in relation to its weight, will perforate the skin at only 124 feet per second. It's easy to believe that such a bullet falling at 300 feet per second could kill you, especially if it struck you in the head. In fact, maybe I need to rethink my dismissive comments about the danger of throwing a penny off the Empire State Building, although I still think the penny's tumbling in the updrafts would render it harmless.

So, Middle Eastern men, gang bangers, etc., listen up! It has been scientifically shown that firing guns into the air for entertainment is not a good idea. Please stop right away. Also knock off with the holy wars and random violence. Thank you.

--CECIL ADAMS


Something that may or may not have been brought up.

Folks seldom shoot straight up - but rather towrads the sky - so the bullet describes an arc, and is travelling fast enough to hurt someone a couple miles away.

As a few threads I looked up pointed out - the many coroners reports would seem to indicate that stray bullets can and do kill people.

Vansquish
04-21-2004, 04:05 AM
I also under the impression that a 2p coin droped off a certain famous tower in Paris makes a rather large hole in the ground.


Actually, that has been scientifically disproven, the coin will reach its terminal velocity during the drop, and it is too low to make much of an impact on the ground, granted it wouldn't be much fun if it hit someone in the head. Since Bullets are more dense and more aerodynamically shaped, I would not be surprised if they reach a higher terminal velocity and that at that rate of descent, they could harm people.


um, trust me dude. science can prove it


Actually science on an atmosphere-less planet could prove it. In this case you do actually have to consider the air resistance, it has a damping effect proportional to the velocity at which the bullet is traveling.

edit: I see people already brought up the Myth Busters coin thing hehe, sorry bout that!

Vansquish
04-21-2004, 04:07 AM
most americans on this site can vouch that atleast once a year, you hear of someone bieng killed or injured from a falling bullet.

I've actually heard more stories about people being smart and using bullets as bits of electrical connections and having them heat up and fire off and injure someone, or even more commonly, people sticking guns in their pants to "holster" them and shooting themselves in the nuts or the ass.

Vansquish
04-21-2004, 04:14 AM
If a bulit is 25 grams then on landing it will have a much higher weight.

weight=mass x gravity

Although the bullit will have much lower speed it will still be pretty heavy on landing.


geekdiggy- I dont think it would be the same speed. Because in this case we have two situations. A bulit going up. And down. When it is going down the only force helping it pick up speed is gravity. And gravitaional force is much lower then the force that the gun exerts on the bullit.

gravity on earth has the force of 10nm per kg. The force in the gun would have to be double that for your theory to work. and it is much higher then that I think.

but I could be wrong

Indeed your logic is not quite right. The force that the gun exerts on the bullet only works during the explosion in the gun itself. After it leaves the barrel, in perfect atmosphere-less conditions, the only force acting on the bullet is gravity, and the force is always pointing in the same direction (down). Thus, while the bullet is moving upwards on its trajectory it the force F=ma has is negative and slows the bullet down until at the top of the arc it reaches a velocity of 0. After that, the same gravitational force continues to act on the bullet except now the bullet is moving in the same direction as the force, so the effect is a positive change and the bullet again speeds up. In essence, the time it takes to go up is the same as that which it takes to come down, and since the force acts for the same amount of time but with opposite signs compared to the bullet's movement, the speed of the bullet when it reaches the level of the gun on the way down will be the same as that when it LEFT the gun on the way up. However....we don't live in a perfect, atmosphere-less environment, so the force exerted on the gun is not just F=ma, but rather has a velocity dependent term which dampens the movement. In other words, it slows the bullet down at some rate proportional to the velocity of the bullet. Aeronautical engineers call it "drag". It is a sort of "air friction". So when the bullet leaves the gun on the way up it will be moving at some rate higher than its terminal velocity, but on the way down the maximum speed it will reach is that terminal velocity. If you want a more in depth description, I can probably look up a website or two or scan some pages from a textbook or two :-)

BADMIHAI
04-21-2004, 08:33 AM
As a few threads I looked up pointed out - the many coroners reports would seem to indicate that stray bullets can and do kill people.



I think there might be confusion between stray bullets and bullets shot straight up. Stray bullets can be just bullets fired in the wrong direction that hurt people. I still don't think falling bullets can hurt people.

blah
04-21-2004, 10:24 AM
most americans on this site can vouch that atleast once a year, you hear of someone bieng killed or injured from a falling bullet.

I've actually heard more stories about people being smart and using bullets as bits of electrical connections and having them heat up and fire off and injure someone, or even more commonly, people sticking guns in their pants to "holster" them and shooting themselves in the nuts or the ass.

nothing wrong with using a bullet as a conenctor for ur headlights.

Vansquish
04-21-2004, 11:54 AM
hehe, I see you've heard that too :-D I never said that bullets don't kill people, all I was trying to say is that IN GENERAL if someone shoots a bullet up into the air it will reach a terminal velocity that will be too slow to do much harm...there are of course exceptions to every rule :-) and depending on how a bullet hit you if it was moving at terminal velocity it could do some pretty serious damage anyway.

nthfinity
04-21-2004, 02:07 PM
for a bullet shot in the air, most loose thier inertial spin after the rotational mass has spun enough air mass. this would cause it to become less stable, and loose many of its aero properties--- thus having a higher Cd. and lower terminal velocity.

also keep in mind, that in the heat of firing a round in some fully auto weapons, the lead looses its shape.

i would venture that a falling arrow would cause much more death and carnage then a falling bullet.

jon_s
04-21-2004, 02:10 PM
I also under the impression that a 2p coin droped off a certain famous tower in Paris makes a rather large hole in the ground.


Actually, that has been scientifically disproven, the coin will reach its terminal velocity during the drop, and it is too low to make much of an impact on the ground, granted it wouldn't be much fun if it hit someone in the head. Since Bullets are more dense and more aerodynamically shaped, I would not be surprised if they reach a higher terminal velocity and that at that rate of descent, they could harm people.


um, trust me dude. science can prove it


Actually science on an atmosphere-less planet could prove it. In this case you do actually have to consider the air resistance, it has a damping effect proportional to the velocity at which the bullet is traveling.

edit: I see people already brought up the Myth Busters coin thing hehe, sorry bout that!

Damn you, I liked that theory lol