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Vengeanze
08-22-2011, 05:59 PM
Saw the liberation of Tripoli on the telly. I mean, yeah celebrate and all but this shooting right up in the air, it's simple physics. Someone is bound to get a falling bullet in the head.

Ze-Jamz
08-22-2011, 06:20 PM
Saw the liberation of Tripoli on the telly. I mean, yeah celebrate and all but this shooting right up in the air, it's simple physics. Someone is bound to get a falling bullet in the head.

Lol, Ive always wondered that, obviously it wont be travelling at the speed of sound but its gunna hurt still right?

tintifaxl
08-22-2011, 09:05 PM
Lol, Ive always wondered that, obviously it wont be travelling at the speed of sound but its gunna hurt still right?

I'd say it can kill easily.

raaaid
08-22-2011, 11:02 PM
i asked the same once in the ubizoo

in newyears eve people gets wounded by falling bullets

but normally not death is not like being shot

Das Attorney
08-23-2011, 12:03 AM
Well timed article here!

http://www.bbc.co.uk/news/magazine-14616491

Blackdog_kt
08-23-2011, 10:07 AM
A couple of years ago i was serving my conscript term as a flak gunner/airport security personnel.

In gun handling and safety training they told us that whenever we want to clear a potential gun jam or make sure a gun is empty before placing it in storage during peace time (which entails taking off the clip, pulling the arming handle and pressing the trigger x2), we should first make sure that if a bullet is inadvertently fired it should be in the direction less likely to cause damage.

First and most used method was to aim in an obliquely placed barrel containing sand, the idea being that the bullet will be slowed down or fragmented before exiting the barrel and even if it does exit, it will go into the soft ground placed underneath the barrel for this purpose.

If a barrel was not present, we were instructed to "empty-fire" at the ground but only if it was soft ground and the angle was shallow, in order to prevent possible ricochets.

If none of these was applicable, we were told to "empty-fire" into the air but sideways (about a 30 degree angle) and not directly up, in a direction with a visibility about equal to the gun's effective range, so that we could first determine there were no materials or people in the way of the bullet within it's effective killing range.

The one thing they stressed most of it all however was "whatever you do, don't aim the gun straight up when clearing jams or practicing safety measures".

A bit of high-school Newtonian physics is enough to calculate that even though friction with the air and the effects of tumbling result in a bullet that comes back down in a probably non-supersonic speed and maybe not with the pointy end facing the ground, it' still a bad idea to fire directly upwards into the air because the downwards speed on the return trip is still big enough to injure or kill.

Sure, it might not be fully effective after it goes through its reversal of trajectory, but getting hit on the head by a chunk of metal that's doing 150-200 meters per second is still a bad idea no matter how one looks at it.
After all, it if was safe people in the age of muskets wouldn't have had so much success killing each other with non-rifled weapons that were shooting round bullets. :-P

Rattlehead
08-23-2011, 05:01 PM
On a similar note:

http://www.youtube.com/watch?v=VyhgC4wF7MU

Guy got lucky (or maybe unlucky, depending on how you look at it.)

Plt Off JRB Meaker
08-23-2011, 05:09 PM
INCOMING!!!!!..............Oh superb Rattlehead,thanks for sharing,brilliant stuff,I still have'nt stopped laughing:lol::lol:

katdogfizzow
08-23-2011, 05:18 PM
Marquels Pledge designed to make holiday safer

Marquel Peters, 4, was killed just after midnight on Jan. 1 after a stray bullet came through the roof of The Church of God the Prophecy in Decatur and struck him in the head during a New Year's Eve church service. Photo provided

DeKalb County officials are urging residents to honor the memory of 4-year-old Marquel Peters and refrain from celebratory gunfire over the Fourth of July holiday and on New Year’s Eve.

William Miller, DeKalb’s director of public safety, said Marquel’s Pledge will create a safer environment during the holidays.

“We’re asking for every single member of the community not to shoot weapons in the air on New Year’s Eve or the Fourth of July,” Miller said. “And even if you don’t, then tell your neighbors, friends and co-workers not to do it.”

Marquel, who was sitting in church next to his mother at a New Year’s Eve Watch Night Service, was killed when he was struck in the head by a stray bullet. Miller said the bullet, which pierced the roof of the church, was either a .44 or .45 caliber and fired from a revolver, a semiautomatic handgun or short rifle.

“We’ve spoken with his mother [Natalee Peters], and she has been supportive,” Miller said. “She doesn’t want her son to have died in vain.”

Family members have struggled to cope with Marquel’s death but “with help from the Lord we’ll make it,” said uncle Gary Peters. “Our desire is that if we can help raise awareness so this doesn’t happen again, then mission accomplished.”

Miller said he has visited about a dozen county businesses that sell firearms to make them aware of the pledge. He also has contacted Wal-Mart by phone and said the company is “on board” with the project.

“We’re asking anyone who sells firearms or ammunition to educate their customers,” Miller said. “We’re asking business owners not to sell ammunition the day before the Fourth of July and New Year’s Eve. We’ve gone door to door to remind them.”

Residents who do fire weapons in celebration could be charged with discharging firearms in public or reckless conduct, Miller said.

“If I can get the anticipated reduction in firing guns, it will be safer to patrol the streets and catch someone in the act of firing a weapon in celebration,” Miller said. “It’s such a long-standing tradition in the south that in years past it’s not even safe for our patrol cars to be out on New Year’s Eve.”

http://championnewspaper.com/news/articles/467marquels-pledge-designed-to-make-holiday-safer-467.html

TomcatViP
08-23-2011, 09:51 PM
If on it's way upward the bullet is a killing item for sure, on it's way back down earth it's not.

Upward: When the bullet had expended its kinetic E it will stop in the air roughly when E_initial =mgh (h is the height reached _ m the mass of the bullet and g the newtonian accel (=10m/s²)and then fall back

Downward : since initial speed in the fall is null and the mass of the bullet is fairly low the potential energy won't provide a tremendous acceleration by itself and the kinetic E won't regain its initial value as the air will prevent the bullet from reaching tremendous speed by the action of the drag.

if we look at the balance of force on it's way back we hve :

W - D = ma with W the weight (= the mass x newtonian accel) and D the drag (=0.5*ro_air*0.5*Pi*r²*v²)

hence a = g - D/m

As D is a function of the speed, the ratio D/m will increase as the square of the speed gained - -> rapidly toward it's peak value : g - and a (the accel) will be down to zero

If I drop myself out of a plane at 5K my terminal velocity will be around 200kph and then will remain cte until something put an end to this state of balanced E.

This is the same for the bullet. It will fall down at v= 2/r * racine square of (1/10Pi) hence 150 to 180kph (100 to 120mph)

Once it reach someone's skull the potential to hurt would be proportional to the momentum m*v see in regard to the head mass (5kg) hence by the conservation of the quantity m*v

V_head = (m_bullet/m_head)*v_bullet -> the speed of the bullet divided by 500 to 1000 time

it's easy to understand that the E generated would be easily coped by an helmet or the skull itself.

{To make a comparison i's like trowing a little stone weighting 3 time more (average speed 60kph) }

So the impact on the skull would generate less than 0.180kph travel speed what won't penetrate any bone hardened body part (:oops:) .

But it can still hurt !!

~S! and best wishes for the newly freed Libya !

Ze-Jamz
08-23-2011, 10:06 PM
If on it's way upward the bullet is a killing item for sure, on it's way back down earth it's not.

Upward: When the bullet had expended its kinetic E it will stop in the air roughly when E_initial =mgh (h is the height reached _ m the mass of the bullet and g the newtonian accel (=10m/s²)and then fall back

Downward : since initial speed in the fall is null and the mass of the bullet is fairly low the potential energy won't provide a tremendous acceleration by itself and the kinetic E won't regain its initial value as the air will prevent the bullet from reaching tremendous speed by the action of the drag.

if we look at the balance of force on it's way back we hve :

W - D = ma with W the weight (= the mass x newtonian accel) and D the drag (=0.5*ro_air*0.5*Pi*r²*v²)

hence a = g - D/m

As D is a function of the speed, the ratio D/m will increase as the square of the speed gained - -> rapidly toward it's peak value : g - and a (the accel) will be down to zero

If I drop myself out of a plane at 5K my terminal velocity will be around 200kph and then will remain cte until something put an end to this state of balanced E.

This is the same for the bullet. It will fall down at v= 2/r * racine square of (1/10Pi) hence 150 to 180kph (100 to 120mph)

Once it reach someone's skull the potential to hurt would be proportional to the momentum m*v see in regard to the head mass (5kg) hence by the conservation of the quantity m*v

V_head = (m_bullet/m_head)*v_bullet -> the speed of the bullet divided by 500 to 1000 time

it's easy to understand that the E generated would be easily coped by an helmet or the skull itself.

{To make a comparison i's like trowing a little stone weighting 3 time more (average speed 60kph) }

So the impact on the skull would generate less than 0.180kph travel speed what won't penetrate any bone hardened body part (:oops:) .

But it can still hurt !!

~S! and best wishes for the newly freed Libya !

Exactly my findings... i was just going to post this TC :)

well done mate

~S~

xnomad
08-24-2011, 07:28 AM
Mythbusters did this already. If you shoot straight up it's harmless it will hurt a little but not kill. If you fire the bullet so it takes more of an orbital trajectory in relation to the ground for example 45 degrees, then gravity doesn't slow it's forward motion as much and it will kill.