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Old July 13, 2013, 09:54 PM   #51
4V50 Gary
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Lawrence of Arabia

T. E. Lawrence, author of Seven Pillars of Wisdom, mentions the Arab practice of celebratory discharging of guns in the air. There were casualties as a result.
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Old July 13, 2013, 10:05 PM   #52
Dixie Gunsmithing
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The US Military did a study on this, though not a very good one by far, and here is a quote from those results:

"As a comparison, the .30 caliber bullet fired in a vacuum at 2,700 f.p.s. would rise nearly 21.5 miles and require 84 seconds to make the ascent and another 84 seconds to make its descent. It would return with the same velocity that it left the gun. This gives you some idea of what air resistance or drag does to a bullet in flight.

"Wind can have a dramatic effect on where a vertically fired bullet lands. A 5 mile per hour wind will displace the 150 gr. bullet about 365 ft based on the time it takes the bullet to make the round trip to earth. In addition the wind at ground level may be blowing in an entirely different direction than it is at 9,000 feet. It is no wonder that it is so difficult to determine where a falling bullet will land.

"Out of the more than 500 shots fired from the test platform only 4 falling bullets struck the platform and one fell in the boat near the platform. One of the bullets striking the platform left a 1/16 inch deep mark in the soft pine board. The bullet struck base first.

"Based on the results of these tests it was concluded that the bullet return velocity was about 300 f.p.s. For the 150 gr. bullet this corresponds to an energy of 30 foot pounds. Earlier the Army had determined that, on the average, it required 60 foot pounds of energy to produce a disabling wound. Based on this information, a falling 150 gr. service bullet would not be lethal, although it could produce a serious wound."

As one can see, the so-called test wasn't that scientific, as they had no way of measuring the actual speed, they were firing in the air, hoping to obtain the hits, and only obtained five, that could have had problems.

Though the calculator gets it off, a good bit, and I knew it would, it admits it does after five seconds, we still have the above average of 300 FPS, as flawed as the test was. I do not think that they can really say that they couldn't produce a disabling wound. They don't even know how those five bullets fell, nor how much the air resistance was over it. Plus, who's to say how dense, or thick, someones skull is? A kids is smaller for that matter.

http://www.loadammo.com/Topics/March01.htm
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Old July 13, 2013, 10:07 PM   #53
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"As a comparison, the .30 caliber bullet fired in a vacuum at 2,700 f.p.s. would rise nearly 21.5 miles and require 84 seconds to make the ascent and another 84 seconds to make its descent.
Please note the emphasized portion of the quote. Guns are not fired in a vacuum in the real world, and atmospheric drag has a very significant effect on the velocity of falling objects. It absolutely can not be neglected in the case of falling bullets if an accurate answer is desired.
Quote:
"Based on the results of these tests it was concluded that the bullet return velocity was about 300 f.p.s. For the 150 gr. bullet this corresponds to an energy of 30 foot pounds.
This are the results that Hatcher obtained with his testing. Since the Army had decided that anything under 60ft/lbs was not likely to be lethal, he concluded that the 30ft/lb impacts were not important. Perhaps this had to do with the protection offered helmets worn by soldiers of the time.

In practice, falling bullets can be and have been documented to be lethal.
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I do not think that they can really say that they couldn't produce a disabling wound. They don't even know how those five bullets fell, nor how much the air resistance was over it. Plus, who's to say how dense, or thick, someones skull is? A kids is smaller for that matter.
Exactly correct. Especially since we have real-world evidence that falling bullets cause fatalities on a regular basis.
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T. E. Lawrence, author of Seven Pillars of Wisdom, mentions the Arab practice of celebratory discharging of guns in the air. There were casualties as a result.
There were also a number of documented deaths and injuries from celebratory gunfire after Kuwait was liberated.

http://www.bbc.co.uk/news/magazine-14616491
"Celebratory gunfire in Kuwait after the end of the Gulf War in 1991 was blamed for 20 deaths."
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Old July 13, 2013, 10:20 PM   #54
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Yes John, but they say 300 FPS, not 150 FPS. Also, the test was flawed, as they didn't really measure anything, I guess they were timing after a shot was off, and it was guessed from five recoverable bullets, and the one which made the dent, was falling with the most wind resistance, traveling bottom down. My guess is that they were some traveling faster, but who knows how much? 400-500 FPS?

Plus, the US military has a reason to not want to show them being lethal, liability wise.

I'm like you, I know they can kill, and so did my cousin who saw it happen.
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Old July 13, 2013, 10:28 PM   #55
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The 150fps figure was from Mythbuster testing and needs to be heavily caveated. Mythbusters assumed that the bullet would ALWAYS tumble since they were unable to recover any rifle bullets in their vertical firing tests and the pistol bullets they recovered showed evidence of tumbling. So they did their "injury simulation" testing based exclusively on the 150fps figure which they determined to be the terminal velocity of a tumbling bullet.

Hatcher's testing proved that falling bullets don't always tumble. His tests results are very valuable since Mythbuster's testing created an apparent paradox by proving that a a tumbling bullet has a very low potential to cause serious injury or death and thus contradicting real-world experience.

Understanding the difference between the three scenarios I explained in my earlier post helps make sense of the apparent paradox created by Mythbuster's assumptions and incomplete testing when compared to documented fatalities from falling bullets.
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Old July 13, 2013, 11:15 PM   #56
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John,

Yes, I understand about Mythbusters. I think their test was just as flawed too.

If we look at the calculator, it shows a theoretical speed of 800 FPS in air (NASA does not describe the mass nor size used, just that it was small, for the calc), and I'm guessing it might at least be half that, and that is a guess, as we don't know what the air pressure nor wind was like that day. The value in vacuum they gave was 2700 FPS, the same as it left the muzzle, and a great height, but they don't quote the actual.

Like the penny falling, it would be according to how it fell. Was it flat, tumbling, or was it slicing down vertically, with the least resistance? I know I wouldn't want to be hit by one, even if it didn't kill me, I'm sure it would do damage.

Also, I don't think I read what the supposed round was supposed to be that hit the child, if it was a 9mm handgun, or something else. It was a handgun bullet that killed my cousins husband, they determined. I think they were probably within 200 feet of the ones firing in the air, sitting on the patio, and she was lucky it wasn't her. Anyhow, I would think it would have been traveling at less speed than a 30-06. I don't know the amount of damage it did, just that he was struck on the top of the head. This kind of stuff kind of makes the military test or Hatcher's moot, especially Mythbusters.

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Old July 13, 2013, 11:16 PM   #57
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So you're saying that an object doesn't gain in velocity when falling, at 32.2 feet per second, squared? In other words, it doubles the speed every second, and that a bullet high in the air, would not hurt you?
You are confused. No bullets fired outside, from the Earth's surface, are fired in a vacuum and so no bullet has the opportunity to fall at 32.3 feet per second, squared. Atmosphere has a significant impact on flight ballistics.

I never suggested a bullet high in the air would not hurt you. Try rereading again. I simply pointed out that your vacuum example was unrealistic to the current problem and that your penny example is nothing but myth.
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Old July 13, 2013, 11:22 PM   #58
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The calculator is not for a vacuum, it is for air, just as John and I have been discussing. If it had been for a vacuum, it would have been much higher, as the military test explains.
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Old July 14, 2013, 09:44 AM   #59
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I want to be sure I understand.

It's ok to fire a gun into the air as long as it's straight up. Right?

A bullet, falling back to earth doesn't really hurt that much. It only leaves a welt for a while. But it won't kill me, that's just anti gun propaganda. Right?

I feel safer now.

...


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Old July 14, 2013, 12:31 PM   #60
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Well, if you fire it straight up - you must stand there till it comes down on you.

Or you can like the Flash, run and get someone else to stand there.

Since most shots aren't straight up - I guess it isn't a plot by the antigun forces.

When I was a kid we played a fun game, we stood in a tight group and the middle guy shot an arrow straight up and then we ran.

The game ceased when we tripped over each other and became a ball on the ground. We watch the arc of the arrow and it landed about 4 feet from the pack. Even eleven year olds thought that the time was out for that game.
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Old July 14, 2013, 01:13 PM   #61
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The whole discussion was pretty useless (I can't believe I bothered to read it all The odds of shooting truly straight up are slim. The assumption must be made that there will be an arc to the bullet path.

Whatever theory you propose, just admit that shooting into the air is bad practice.
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Old July 14, 2013, 02:19 PM   #62
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That says it all. Thanks for all the good technical discussion.

Remember your tinfoil hat will not stop a falling round - sorry.

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