I have read about similar tests, and the "Myth Busters" ( I know Dave, their gun handling practices scare you) had done a test as such using the 9mm I don't recall the exact ft-pounds/speed result but I am sure it was similar to these.
Last year, during the 4th of july holiday in a neighboring city, a person was struck by a falling bullet while sitting in her covered patio room. The bullet punched thru the exterior awning and struck her knee. Not a life threating wound, but it seems the bullet had enough power to cause serious injury if she had been sturck in the head!

The problem is NO ONE shoots perfectly straight up so you end up with a ballistic trajectory and a very deadly round coming back to earth.

To Tom: The heavier bullet would carry much farther and drop long after the .22 had fallen to earth. Greater weight, greater momentum. The same reason a 16-inch naval gun will outrange a 14-inch.

I always wondered when I saw those towel-wearing idiots on CNN shooting their AKs into the air. "Holy war! Holy War!" *plink, plink, plink* "Holy s***!"

To Mark: No, I am not. If you, or anyone who is scientifically aptituded can add anything to this issue, have at it.

In order to it the ground at the same time, they would have to have the same vector.

If and two bullets were dropped straight don from the same height, they would in fact hit the ground at the same time.

However, this is not the case when two bullets are actually fired out of a gun; even if the centerline of the bore is perfectly perpendicular to gravity; because the force (actually forces) acting in the X axis, and the force acting in the y axis (graivty) prduce a vector that is NOT 10.8 meters per second per second straight down. Additionally, there is an aerodyanmic element to the forces in question that must be considered; as it effects bost the positive x axis and y axis forces (effectively adding negative x and negative y elements to the vector).

Whenever multiple forces meet, there is a vector that is the sum of those forces. In this case we have the force of the bullets propulsion, the force of gravity, the force of the air against the bullet, and the force of gyroscopic inertia (from the bullets rotation).

The resultant vector is dependent on the total force in each direction, which is dependent on the mass, velocity, and firing angle (or in the case of the gyroscopic forces rotatonal velocity) of each bullet; as well as local gravitational variation (gravity varies with altitude a ballistically significant amount), air pressure, temperature, and humidity (all ofwhich effect air density).

Now, these differences start off small, but the longer the bullet is in flight, the more they make a difference.

If you were to fire two guns perfectly horizontally from a standing position with 5000 feet of level ground in front of you for example, the bullets would in fact fall to earth at functionally the same time (a few microseconds difference perhaps).

However, if you fired from the edge of a canyon with 2 miles of clear space in front of you and a 5000 foot drop below you, the result would be very different.

This can be simulated with ballistic software if you'd like to take the trouble, but really it's just wonkery.

That is why I put Hatcher's Notebook on my list of gunbooks in a post a while back.
Now, we are talking about bullets fired straight up and falling back to earth reaching terminal velocity.
With bullets (service weight) of 150 grains or less. Energy is about 30 foot pounds or less with lighter weight projectiles. Remember, 60 footpounds being necessary to achieve a serious wound. Most all stories about stray bullets have a hrizontal component to them making them dangerous and lethal.

That said, (again refering to Hatcher's Notebook, a artillery shell aor naval gun, fired straight up would also reach the terminal velocity, but do to it's weight, would really mess up your day.

Here's the physics as best I recall it.

On earth the acceleration is 9.8 m/sec-sec. 10 is a ballpark approximation.

In a vacuum, two bullets of substantially different weights and at an identical and suborbital velocity would hit the ground at the same time. Thus the .22 would strike ground at the same instant as a heavier round.

That they don't is because in general drag robs energy from the .22 bullet faster than the larger bullet. Of course bullet shape, tumbling and all other manner of things can affect same.

Two bullets will drop at the same speed - in a vacuum. In reality, weight, shape, drag, etc., all come into play; hence different ranges for different rounds even at the same initial velocity/ angle, and different terminal velocities for different rounds fired straight up.

Remember, in theory, theory and practice are the same, in practice, they're different.

OK, after typing this, I see the previous person said the same thing, so I 'second' his explanation.

I read all of you guy's smart-guy posts and tried the experiment for myself.

Shot the wife's vaccuum four times with no aparent difference in drop speed.

I do gotta buy a new vaccuum now.

I would not want to be struck with a falling bullet returning to earth. the 30 Foot Pounds energy is similar to the recoil of a 300 Remington Ultra Magnum, but he diameter of the projectile is less than 0.45 inches. It would be like concentrating the recoil energy into a small stud on the stock. And on what part of your body would like to have this applied ?

To all safe hunters and shooters, dont try this dumb stunt (shooting straigt up into the air), and seek safe shelter if anyone around you tries it. Leave it to the other cultures to perform this dumb stunt, and risk the well being of their citizens. If you aren't sure of the outcome, don't take the shot. Safe shooting, Richard V.T.

MAN NOW I HAVE A HEADACHE!!!!