MythBuster question.

only thing i can think of that could make a difference is there is a cross wind

airgun pellets tend to climb (or slow dropping) in a right to left wind (assuming pellet is spun clockwise as you look at it from behind)

and fall in a left to right wind its fairly minimal and maybe only on pellets at longer ranges
 
By the way Hornet 6 your photo is a moth that is pretending to be a hornet...just thought you should know. It is a type of Clearwing!:D

Really, I took it after fishing the thing out of a lake as it drifted past, it survived after drying out in the sun for a while.

Neil :)
 
Assuming the gun is fired completely level, you can consider that the only force exerted on them in the vertical plane is that of gravity- an acceleration of 9.81ms-2. This is because you can resolve the force acting on the projectiles into a horizontal and vertical component, completely eliminating the horizontal velocity from the equations. after that simply use s=ut+.5at^2 to establish the time required for them to hit the ground. BC will have no effect and neither will any other variable which influences the horizontal velocity, as this was disregarded when we resolved vertically. Both will have similar terminal velocities due to their similar mass and air resistance and assuming that air temp etc. is constant will attain it within a fraction of a second of each other, thereby proving that the height dropped from has no influence on the results.

But what about the Coriolis effect?:doh:
 
But what about the Coriolis effect?:doh:

What about it? The coriolis effect can be modelled as a lateral force on the projectile, i.e, it effects the bullet impact point to the left or the right dependent on the rotational axis of the projectile relative to the rotation of the earth (as viewed from directly behind the projectile), but it will have only a very tiny effect on its vertical path as it doesn't change the velocity, air resistance, bullet bc or the acceleration due to gravity. Therefore, it will have very little influence on the time taken for the bullet to hit the ground. look at it this way; 2 kids are throwing a ball to each other whilst being rotated on a roundabout. To their viewpoint, the path of the ball curves in the lateral plane due to the rotation, but it will still fall at 9.81ms^2, just the same as every other object in freefall that is yet to reach terminal velocity (minus a small amount for air resistance).

Edit: Having done a little more reading on the subject, it would appear that a related effect, called the Eotovos effect, can influence the vertical trajectory as well, resulting in a very small change in the impact time to the ground. However, this was applied in the case of ballistic missiles travelling 2000miles+ as well as the WW1 Paris gun firing over 120km and so will probably have no observable effect on a bullet travelling over much shorter distances. Please also note that this hypothesis is based on a basic knowledge of physics and a few assumptions, and so should be treated with a healthy degree of sceptiscism. :)
 
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