I was having this conversation and decided to do the math... and its pretty much impossible..
Although so many people disagree so Im posting this here....
The only thing I didnt take into account was the increased mass groing from something like a .22lr shell to something like a 45acp shell and the inertia it carries, but it would be negligible at best. and with a larger shell breakage of skin could accure and youd have one hell of a goose Egg on your head but you would be ok.
heres what I figured out
Quote:
Terminal velocity of average bullet = 200mph or 293FPS
Red ryder BB gun MAX muzzel velocity = 350 FPS
Muzzel Velocity of average .22lr round = 1200fps
9mm muzzel velocity = 990 - 1350fps
45acp muzzel velocity = 1450FPS
.223 average muzzel velocity = 2396fps
Your average bullet will fall at least 57 FPS slower then that of a BB leaving a low powered Red Ryder BB gun
Assuming it can reach TV on the way down (the max speed it can fall at)
TV of an average bullet is almost identical to the muzzel velocity of the lowest model Airsoft toy gun made wich will only sting a bit if shot a point blank range.
SO getting shot from a spring powered plastic Airsoft rifle would be about the same as getting hit my a bullet falling from the sky.
Wich is not fatal or even seriouse.
Argue all you want
but trust me my math is 100% correct I made sure of it...
Discuss
How was terminal velocity determined? That's obviously not for a bullet pointed "forward", but rather falling on its side/end-over-end/whatever else.
Now, if the bullet was fired at enough of an angle from straight-up, the trajectory could keep the round facing "forward", which obviously retains its momentum and would have a MUCH higher terminal velocity.
IIRC, mythbusters already hit this one, and there are confirmed reports of people being killed by falling bullets, even after the round broke though a roof.
fortune cookie say: better a delay than a disaster
Terminal velocity was figured with the shell falling basically straight down (fired up in the air) and regardless of which way its pointed. thats the fastest one is gunna fall from the sky.
Also you need to remember... by the time gravity takes over its not going to be really spinning anymore and the pointy side of a bullet it the lightest side so theres nothing that would cause it to fall point down and stay there. Also... the spinning of the bullet does not make it fly through the air faster... all that does is stabilize the round.
btw, myth-busters for the most part are tards... they are not the final say in anything and I have seen them wrongly conclude things more then once.
At the time I was arguing that no one could get hurt by firing a .22lr in the air..... wich they cant.... the lead doesnt have much more mass then a pellet or BB... and I've been shot by them traveling over 4 times as fast as a 22 round could fall and it just stung a little.
A 22 round doenst have the power to go through a roof at 1200fps fired from a gun let alone falling from the sky..
Now if something heavier like a 9mm or 45cal round actually hit you in the head at close to 200mph it would have the internal energy to do some damage? yes... but actually bust through your skull into your brain? No.
Now a gun fired laterally is completely different..... also terminal velocity refers to freefall btw...
If you fire a gun even at an upward angle but laterally along the ground chances are that gavity is going to pull it back down to the earth quicker and its going to hit the ground at a faster speed.... but thats a whole other set of math... first you have to take into account the effective range of the projectile..... then you have to fiqure out how far away it will hit the ground based on the trajectory vs speed and rate of deceleration and see if it will still be in that effective range or not amongst trying to figure out how fast it will be moving... (effective range = fatal range for the most part)
But regardless.... if you got into the trajectory where it was deadly it would be to the point that you could hardly say the bullet "fell from the sky" anymore and we would be in the range of a person actually getting shot, not hit by a FALLING bullet.
Im talking solely about firing a round straight in the air or at least up to a 40 degree angle in the air.. in wich case by the time it hit the ground the only thing that would be propelling it would be gravity...
What is the point of this thread exactly? Are you trying to defend yourself for letting off shots on New Year's or something? Even if it doesn't end in death, is assault acceptable?
Weebel wrote:Terminal velocity was figured with the shell falling basically straight down (fired up in the air) and regardless of which way its pointed. thats the fastest one is gunna fall from the sky.
Weebel wrote:Also... the spinning of the bullet does not make it fly through the air faster... all that does is stabilize the round.
Put these two statements together, and then re-think them. Only VERY basic aerodynamics knowledge is required here.
Weebel wrote:Also you need to remember... by the time gravity takes over its not going to be really spinning anymore
Why not? Under all conditions? There is very little friction applying a resistive moment along the rounds rotational axis. Conservation of momentum is a strong argument here.
Also, gravity takes over immediately
Weebel wrote:and the pointy side of a bullet it the lightest side so theres nothing that would cause it to fall point down and stay there
*facepalm* for Isaac Newton on this one... He's probably ROFL 6ft under.
Weebel wrote:btw, myth-busters for the most part are tards... they are not the final say in anything and I have seen them wrongly conclude things more then once.
Agreed 100%. However, you really should watch the episode. I think you'll agree with this one 99%, as they made the same mistakes you have
Weebel wrote:At the time I was arguing that no one could get hurt by firing a .22lr in the air..... wich they cant.... the lead doesnt have much more mass then a pellet or BB... and I've been shot by them traveling over 4 times as fast as a 22 round could fall and it just stung a little.
That might have been your argument in a previous conversation, but clearly not in this thread. Also, you're making a LOT of generous assumptions and rationalizations, a "long-shot" from a scientific theory.
Weebel wrote:A 22 round doenst have the power to go through a roof at 1200fps fired from a gun let alone falling from the sky..
More assumptions...tisk, tisk. What's the roof made of? I believe one of the instances was a tin shed. I think you can see where I'm going from this, not everyone lives in a concrete-roofed underground bunker. Yes, I realize a 22 is the equivalent of a 5lb hammer at 7mph
Weebel wrote:Now if something heavier like a 9mm or 45cal round actually hit you in the head at close to 200mph it would have the internal energy to do some damage? yes... but actually bust through your skull into your brain? No.
45 at 200mph = 5lb hammer at 15mph. If the end of that hammer was pointed? Sounds like it could be a skull-buster to me. However, I'm not about to do the burst-strength calculations to prove it lol.
Weebel wrote:also terminal velocity refers to freefall btw...
Would you like a dictionary?
http://dictionary.reference.com/browse/terminal+velocity
Weebel wrote:If you fire a gun even at an upward angle but laterally along the ground chances are that gavity is going to pull it back down to the earth quicker and its going to hit the ground at a faster speed.... but thats a whole other set of math... first you have to take into account the effective range of the projectile..... then you have to fiqure out how far away it will hit the ground based on the trajectory vs speed and rate of deceleration and see if it will still be in that effective range or not amongst trying to figure out how fast it will be moving... (effective range = fatal range for the most part)
The first sentence is hilarious to say the least ("gravity pulling it faster" lol). I don't like your "effective range" concept, as wound location determines lethality of a round more than target distance.
Weebel wrote:Im talking solely about firing a round straight in the air or at least up to a 40 degree angle in the air.. in wich case by the time it hit the ground the only thing that would be propelling it would be gravity...
I don't understand why you are so incosistant with whether or not you choose to apply conservation of momentum to a horizontal plane... You did it in the previously quoted section, but this time not?
Weebel wrote:But regardless.... if you got into the trajectory where it was deadly it would be to the point that you could hardly say the bullet "fell from the sky" anymore and we would be in the range of a person actually getting shot, not hit by a FALLING bullet.
I SEE THE PROBLEM!!! You're defining "falling" by whether or not the injury results in death.
Wow, you've taken a no-lose position by applying a weak semantical argument lol.
Also, please stop saying "math", as you haven't really done any yet lol. It's like Taetsch saying "Fact." I know it might convince the ignorant that you know what you're taking about, but it doesn't make it true...
fortune cookie say: better a delay than a disaster
66 feet per second per second.
Every year in Central Florida around New Years, the news agencies remind people not to shoot their guns into the air to celebrate. The reason being was two incidents that happened two years in the row. One being a
man that died after being hit by a falling bullet and another where a woman was
hit in the eye. So no need to go into the math, when there are documented cases of it happening.
I work on Wall Street, but didn't force you to take out a loan you couldn't afford.
The TV of a projectile changes depending on its shape.
If you sky dive and you go spread eagle your TV decreases as you have more wind resistance. Now take that same sky diver and make him a pencil shape, his TV increases. You cant arbitrarily say that a certain bullet has a certain TV.
Second thing, mass of the bullet has everything to do with how much damage it can inflict. The higher mass means more momentum which means more penetrating power. Say I throw a baseball at your head at 25 mph, its going to hurt but it most cases it wouldnt kill you. But lets take a 12 lb bowling ball and shoot it at your head at 25 mph, you probably will feel that quite a bit more. So youre missing the fact that a .45 caliber round weighs significantly more than a standard airsoft BB.
Edit: If you want to get technical, unless the bullet is in a perfect up and down situation where no sideways movement is occurring, it will still retain some of the velocty it was fired with as well as the rotation of the bullet as long as the velocity of teh bullet doesnt drop enough that it loses the ability to retain rotation
Edited 1 time(s). Last edited Monday, February 01, 2010 4:00 PM
Gravity won't "pull the bullet to the ground faster". Gravity will always accelerate the bullet at roughly 32.2 ft / sec / sec as I think OHV notec was pointing out. The bullet shot at angle more parallel with the ground will only come back to earth in less time because it it doesn't travel as far vertically.
You have to remember that velocity, and the forces on the bullet are vectors. If you shot the bullet at a 45deg angle from the ground, it's horizontal speed is approximately 70% of the muzzle velocity and it's vertical speed is also about 70% of muzzle velocity. Even with air resistance, when the bullet comes back to earth it still have a horizontal speed of roughly 70% of the initial muzzle velocity, which alone would be enough to kill someone, plus the vertical velocity equals leathality. Remember: Vx^2 + Vy^2 = V^2 (Thank you pythagoras)
Also if the bullet is more horizontal when shot, it is more likely to maintain it's flight characteristics not not start to tumble.
Like Sundown said, only in an ideal case where the bullet remained perfectly vertical in it's flight path would the "not killing you" even be plausible.
And I totally agree, the Mythbusters are starting to seem little stupid, like the episode where they dimpled the car like a golf ball. Of course it had less drag, if it didn't why would golf balls have dimples? It drove me crazy that they were surprised. They the B team is starting to do a lot of things that can't be properly objectively tested, but this is beside the point.
66 feet per second, per second.
is this seriously being debated? seriously?
Bore x Bore x Stroke x .7854 x # of cylinders = The answer to all of this
I win.
sndsgood wrote:mythbusters debunked this awhile ago.
Right, they were measuring rounds fired straight up. At the end though, they couldn't account for the ACTUAL OCCURANCES. Not all shots are fired totally vertically.
fortune cookie say: better a delay than a disaster
What did Mythbusters conclude as to the terminal velocity of the projectile falling to earth? In other words, at what speed did aerodynamic forces arrest further acceleration?
OK I shouldnt have said gravity will pull it to the ground faster.... what I meant was it will hit the ground sooner.
Everything from the original post was used going by the lead from a .22LR round and I stand by the fact if you shoot one of those rounds streight in the air, unless you looking up and it hits you in the eye... its not gunna kill you.
Yes I realize something like a 45 or 9mm round has more weight and is completely different...
To be honest.... I was just bored and I know this was something that would get you all going and thats really the only reason I posted it.... just to mess with you guys and get you all into a nerd rage LOL
It worked and im happy
Seriously though.... I just wanted to end the political crap for a bit.
Truth,,,from consequences wrote:What did Mythbusters conclude as to the terminal velocity of the projectile falling to earth? In other words, at what speed did aerodynamic forces arrest further acceleration?
im not sure i remember it was about a year ago when i had seen it, but they determined that when it reached its terminal velocity on the way down it didn't have the force to kill anyone.
which reminds me of being up in tall buildings or towers people saying if you dropped a penny from this height blah blah blah it would kill a person.
http://www.flickr.com/photos/sndsgood/ https://www.facebook.com/#!/Square1Photography
OK. Sounds fair enough...the density of air near the earth's surface would cause significant enough drag to prevent the bullet from attaining a lethal speed, if shot straight up to the degree that gravity arrests its upward travel, and it then begins to fall downward.
That being said, I do agree with earlier posts which note that the real problem with potential injury is that most such bullets are fired at a trajectory that is less than straight up, to the extent that they do not lose all of their forward speed before they achieve apogee and then come back to earth in a downward path. These are the potentially lethal ones.
It's all kind of a moot point anyway, I suppose, in that anyone who fires any gun randomly, whether straight up or not, is risking injuring someone. In cases where it's not straight up, they risk killing someone. In all instances, it's pretty stupid. Unfortunately, some stupid people own guns. Before gun fans take umbrage, I must emphasize that not ALL gun owners are stupid, nor are all stupid people gun owners. Thank God!
Weebel wrote:OK I shouldnt have said gravity will pull it to the ground faster.... what I meant was it will hit the ground sooner.
Correct, because it will not actually go as high in the first place.
Weebel wrote:Everything from the original post was used going by the lead from a .22LR round and I stand by the fact if you shoot one of those rounds streight in the air, unless you looking up and it hits you in the eye... its not gunna kill you.
I will agree that you would have to be very unlucky to be killed by a 22 fired straight up.
Weebel wrote:To be honest.... I was just bored and I know this was something that would get you all going and thats really the only reason I posted it.... just to mess with you guys and get you all into a nerd rage LOL
Yes, any physics/engineering discussion will get me going lol. See "110% VE" thread for the best example
fortune cookie say: better a delay than a disaster
Truth,,,from consequences wrote:OK. Sounds fair enough...the density of air near the earth's surface would cause significant enough drag to prevent the bullet from attaining a lethal speed, if shot straight up to the degree that gravity arrests its upward travel, and it then begins to fall downward.
That being said, I do agree with earlier posts which note that the real problem with potential injury is that most such bullets are fired at a trajectory that is less than straight up, to the extent that they do not lose all of their forward speed before they achieve apogee and then come back to earth in a downward path. These are the potentially lethal ones.
It's all kind of a moot point anyway, I suppose, in that anyone who fires any gun randomly, whether straight up or not, is risking injuring someone. In cases where it's not straight up, they risk killing someone. In all instances, it's pretty stupid. Unfortunately, some stupid people own guns. Before gun fans take umbrage, I must emphasize that not ALL gun owners are stupid, nor are all stupid people gun owners. Thank God!
yeah there tests were based on the bullet falling, not at an arc which im betting when most people are just shooting up into the air are doing it at an angle. but when your figuring in an arc and that the bullet is still being propelled by the intial gun blast it kinda chances the argument from being hit by a"falling" bullet. to being shot by a bullet that may not have the full force of a shot.
http://www.flickr.com/photos/sndsgood/ https://www.facebook.com/#!/Square1Photography
I'm a gun owner, and I don't believe guns (save for clearly military-style weapons) should be kept from the public. But anyone who fires a shot at random, without knowing where it will land, is a complete assh0le, and does not deserve to own a gun.
Change the round from a .22LR fired into the air to my .458 Win Mag fired into teh air. Using a "heavy" estimate of 30gr for the .22 my .458 uses a 500gr bullet. Fired at the same angle with the same trajectory (I know they wont follow the same path and hit in teh same place) the .22 may or may not kill you, but I would bet the .458 would, this is assuming the bullet struck you in a vital area. I dont thing I would even want to be struck by a 500gr bullet free falling at terminal velocity.
At least your finally understanding that Im talking about firing it straight in the air and not at an arc... so the thing would be falling as if it was dropped out of a helicopter...
And yes.... the whole conversation got started because "someone" was firing a 22 revolver in the air on the 4th of july LOL
you all fail.
you're believing that a bullet's arc path is the same as a missile or an arrow.
an arrow reaches distance and maintains power and stability because of the flights opposite the head. a bullet does the same from spin.
you also forget that gravity pulls from center of mass, and always straight down-- an arrow appears to have an arc because the center of mass is in the center of the arrow and the arrow rotates along this point until it runs out of momentum.
forward momentum of the bullet; fairly regardless of gravity's pull at any launch angle; is determined by it's propellant. so if you fire a gun at 0 degrees, and an exact duplicate at 33 degrees, their total time of bullet travel will remain the same--the difference is that at 0 degrees the bullet runs out of energy at, 1000 yards to the right of the gun, but at 33 degrees, the bullet runs out of energy at 300 yards right of the gun; except that it is now 600 feet in the air. the bullet does not maintain an arc like an arrow does since it is rotationally stabilized, it begins to tumble after it's rotational energy has run out due to friction, at which point gravity will continue to pull on it straight down; to terminal velocity even though the bullet appears to be moving away from the muzzle--on an arc, that is not symmetrical. steep on the fired side and shallow on the falling side.
anyway, a bullet cannot fall faster than terminal velocity--which is nonfatal--unless fired at a specific range of angles that, like someone else basically said, don't count as firing it into the air. at those angles the bullet is travelling instead of falling.
KevinP (Stabby McShankyou) wrote:you all fail.
That's a strong statement considering what follows it...
KevinP (Stabby McShankyou) wrote:you're believing that a bullet's arc path is the same as a missile or an arrow.
I'm pretty sure I was clear on this one, but I'll let you attempt to explain it again...
KevinP (Stabby McShankyou) wrote:an arrow reaches distance and maintains power and stability because of the flights opposite the head. a bullet does the same from spin.
Congratulations! You've managed to re-state what has been brought up already, on more than one occasion in this very thread... Just for craps and giggles, I'd like to point out that some arrows are ALSO designed to spin.
KevinP (Stabby McShankyou) wrote:you also forget that gravity pulls from center of mass
Well, not technically true, but the simplification can be made under ideal conditions. I'll call it acceptable for this discussion
KevinP (Stabby McShankyou) wrote:and always straight down
Also, not technically true. But, also certainly acceptable for the conversation at hand.
KevinP (Stabby McShankyou) wrote:an arrow appears to have an arc because the center of mass is in the center of the arrow and the arrow rotates along this point until it runs out of momentum.
WOW. Where to start with this... I guess I'll give you the benefit of the doubt and ask you to clarify "center of the arrow". In relation to the main axis how?
KevinP (Stabby McShankyou) wrote:so if you fire a gun at 0 degrees, and an exact duplicate at 33 degrees, their total time of bullet travel will remain the same
Definitely not true. Not even sure why you would think this. High school physics here... t_of = 2*v_i*sin(angle)/g + sqrt(2*height of gun/g)
KevinP (Stabby McShankyou) wrote:the difference is that at 0 degrees the bullet runs out of energy at, 1000 yards to the right of the gun, but at 33 degrees, the bullet runs out of energy at 300 yards right of the gun; except that it is now 600 feet in the air.
Seriously? Please clarify on "energy", as I REALLY hope you don't mean total energy...
KevinP (Stabby McShankyou) wrote:the bullet does not maintain an arc like an arrow does since it is rotationally stabilized, it begins to tumble after it's rotational energy has run out due to friction, at which point gravity will continue to pull on it straight down; to terminal velocity even though the bullet appears to be moving away from the muzzle--on an arc, that is not symmetrical. steep on the fired side and shallow on the falling side.
You got that last part backwards, and you'd better replace "appears to be" with "is"... but I don't think anyone is disputing the rest
KevinP (Stabby McShankyou) wrote:anyway, a bullet cannot fall faster than terminal velocity--which is nonfatal--unless fired at a specific range of angles that, like someone else basically said, don't count as firing it into the air. at those angles the bullet is travelling instead of falling.
More half-truths. As has been pointed out by people on both sides of this, certain heavier rounds can be fatal even when tumbling.
And, as I said to Weebel, I find drawing a line at "falling" when the round starts tumbling to simply be an "out" for this one. I consider anything fired aimlessly into the air with no intended target to be "falling".
For the most part, this whole thread is a potato/potatoe argument.
fortune cookie say: better a delay than a disaster
