Falling ball vs thrown ball in a atmosphere, which hits the ground first.

[sbunny8]

The bullet produces lift because of its nose-up orientation relative to its downward trajectory. But the amount of the lift can never be larger than the weight of the bullet. It slows down the bullet’s drop but it cannot make the bullet move horizontally with no drop at all, nor can it cause the bullet to rise. The lift only partially offsets the force of gravity.

[enipla]

But wait a minute. A perfectly conical shape will not provide lift when falling from a flat trajectory in forward motion. An airplane wing produces some lift (really a vacuum on the top) due to the Bernoulli effect (not as much as they told us, it’s all about angle of attack).

Why would the perfectly conical shape of a bullet provide lift because of velocity?

Are you saying that the very act of falling while the gyroscopic effect keeps it level to the ground provides lift? That (lets take a 30.06 for example) the act of falling 3"s in one hundred yards produces a vacuum on the top of the bullet to provide lift? On a conical object?

[Machine_Elf]

@enipla

But wait a minute. A perfectly conical shape will not provide lift when falling from a flat trajectory in forward motion. An airplane wing produces some lift (really a vacuum on the top) due to the Bernoulli effect (not as much as they told us, it’s all about angle of attack).

Angle of attack is in effect for the bullet, too. Once it begins falling, it’s got a non-zero angle of attack. If it helps you visualize this, imagine tilting your head so that the bullet’s trajectory appears to be horizontal in your view, and then the bullet will appear to be pointed slightly nose-up, i.e. a positive angle of attack. Wings are exceptionally good at producing lift, but any object with non-zero angle of attack will produce some lift:

@Wikipedia

Any object with an angle of attack in a moving fluid, such as a flat plate, a building, or the deck of a bridge, will generate an aerodynamic force (called lift) perpendicular to the flow. Airfoils are more efficient lifting shapes, able to generate more lift (up to a point), and to generate lift with less drag.

@enipla

Are you saying that the very act of falling while the gyroscopic effect keeps it level to the ground provides lift? That (lets take a 30.06 for example) the act of falling 3"s in one hundred yards produces a vacuum on the top of the bullet to provide lift? On a conical object?

Very slight, but yes. If it helps, try to imagine the bullet as a wing with a very, very low aspect ratio (i.e. it has a wingspan much, much shorter than its chord). sbunny8’s simulation work shows that the difference in drag for a horizontally-fired bullet (vs. a dropped bullet) is also very, very small, but it’s a real effect. The longer the bullet is airborne, the steeper the descent angle (= the angle of attack) becomes, and the more lift it generates. Never enough to bear its entire weight, but enough to change its trajectory from a pure parabola into something just a little bit more like a hyperbola.