ORIGINAL: driftrider
Nomercy,
Then the real question is this...does the magnus effect due to a strong crosswind coming from the correct direction create enough lifting force to balance or overcome the force of gravity, under REALISTIC shooting conditions?
If it does, then a bullet could in fact experience enough body lift to actually climb above the plane of the barrel. If not, one could say that the force simply acts to retard the decent of the projective by cancelling out some of the accelleration created by gravity (like a parachute).
Mike
I agree driftrider. Considering that the viscosity of atmosphere is so minute compared to any liquid. And even in hurricane force winds (which I hope no one will be shooting at a deer then) and the rate of rotation is still only 1 in 10 inches for most rifles (fast time true, but not likely fast enough) and considering the tiny amount of surface area involved compounded by the density of the bullet (it's going to take a lot of lift to noticeably affect something made of lead and copper) that the Magnus effect would probably so small that it would only retard the rate of decent and even then you'd probably need to borrow a lab and a few NASA techs to separate the difference from standard deviation. Here's the real kicker though, using the old .30-06 as an example, the bullet is not just spinning in space it leaves the barrel at 1,984 MPH and if shooting in a 100 MPH crosswind the net effect would be a 0.05% total wind direction change over the surface of the projectile from shooting in calm conditions. That's about 9 degrees from head on and that would definitely not be enough, in my opinion, to generate the Magnus effect in any measurable quantity. Now you're no longer talking about the rotation being perpendicular to the air current, it's nearly parallel to the air current. Keep in mind that's with 100 MPH crosswinds! That's my opinion. But hey, it's been a long time since I was at Purdue and Nomercy, I'd love it if you'd run the numbers and prove me wrong (not with out debate of course
) because I want above all else to learn. In fact if you can demonstrate this does indeed have a quantifiable and meaningful impact on ballistics it will certainly only enrich my knowlege as well as others who read this board and after all that's why most of us are here.
I still believe that the bullet NEVER rises above the plane of the barrel! By the way, every physics model used by "ballistics software" I've tried out agrees with me on that one. If you plot bullet drop you wont find the bullet rising to a positive number at any point. Who knows maybe they "don't of what they speak" either (to paraphrase your post), in which case you could set us all straight.