Mythbusters could not find the .30-06 rounds they were firing into the air so they had a baloon drop them from 400 feet for comparison. 150 grains dropped from 400 feet is not going to be much different than a 9mm dropped from the same distance which they used as comparison as both weigh very similar and 400 feet is not much time to speed up. From 400 feet they would only be traveling at roughly..let me figure it out: assuming a vacuum (wind resistance changes it, but not enough at 400 feet to matter as you will see) something falls at about 9.8 meters per second faster every second, -resistance which increases as speed goes up. That is about 29.4 FPS. 400 would be covered before it sped up much. In a perfect vacum without air resistance that distance would be covered before it got up to 147 FPS, air resistance reducing it even further. 1 second 29.4,2 seconds 58.8, 3 seconds, 88.2, 4 seconds, 117.6, 5 seconds, 147. 441 feet would be traveled in 5 seconds in a vacuum. Only allowing it to get up to 147 FPS. So of course thier demonstration did little damage. 155 grains falling at 147 feet per second negative air resistance would not pose a great threat. Add many many more seconds as a rifle round would actualy take to return to earth as the round approaches its terminal velocity and your talking a lot more damage.
They also measured how far it went into the ground which is an absolutely poor method. You can fire a powerful round into the ground or a low powered round into the ground and depending on the makeup of the ground and how rugged the bullet not have a great difference. Even thier own earlier tests showed fired into ballistic gelatin thier rifle round (a .30-06 which is far more deadly) went through a single block and thier 9mm round went through three blocks. Does that mean the 9mm does more damage? Most certainly not.
So mythbusters was very false. Given thier own data for the amount of seconds the 9mm rounds took to come back to earth which was 39 seconds, if we assume most of that time was spent coming back down, lets say 75% of the time was coming down, as going up it went up with full speed (of course slowing as it went higher), and came down at falling speed. 75% of 39 would be 29.25. In 29.25 seconds in a vacuum that round would speed up to 29.4X29.25= 859.5, which is far faster than it's terminal velocity in atmosphere, meaning that with that much margin of error it is pretty safe to say it would be close to its terminal velocity when it returned even with air resistance and drag, and that the
rifle round would have definately reached its terminal velocity.
If someone wants to figure the terminal velocity of it go ahead, but it is going to be a around few hundred feet per second. Meaning that the 400 foot test that would not have allowed it to even approach 145+ FPS was VERY innaccurate.
Even if only 50% of the 39 seconds it was in the air was spent coming down that would equate to 19.5 seconds falling reaching a speed of 573.3 FPS in vacuum which is faster than its terminal velocity in air, meaning it likely would reach close to it's terminal velocity coming down. So it would still be going a few hundred FPS when it impacted, far greater than the under 145 FPS allowed in the 400 foot drop test. That is just the 9mm and not even the rifle round that would surely reach its terminal velocity.
They even estimated the 30-06 was going to around 10,000 feet, and the 9mm to 4000 feet. Plenty of falling distance to reach terminal velocity according to thier own math.
Mythbuster's busted. The idiots are just lucky they were not hit by one of the falling 30.06 rounds instead of being unable to find them.
Angle and trajectory makes them much deadlier, but heavy bullets that get high can be deadly even falling straight down.
P.S. Here is a link describing the steps taken in the mythbuster episode proving everything I said
http://kwc.org/mythbusters/2006/04/episode_50_bullets_fired_up_vo.html
They VERY incorrectly determined the terminal velocity of a round. There is a simple formula you can use to determine terminal velocity but whatever they did they determined less than half of its real terminal velocity as the terminal velocity. Terminal velocity for a Sky Diver is over 150 FPS which is as fast as they determined for a bullet with much great sectional density, far less drag/mass ratio etc.
Correct math gives a 30-06 round around 99m/s or 297 feet per second velocity. Over double the speed the 400 foot drop test would reach in a perfect vacuum, nevermined with some air resistance.
Here is the formula for terminal velocity :
http://www.karlscalculus.org/l12.1.html
) could kill someone. It is definately going to cause property damage. Near where I live many outdoor shooting ranges were closed down because idiots were shooting skeet with rifles(though they have a trajectory at that angle and so were much more dangerous) and people living within a few miles complained of dead animals and damaged property.
