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Old July 13, 2013, 10:05 PM   #52
Dixie Gunsmithing
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Join Date: April 27, 2013
Location: Ohio
Posts: 1,923
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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