Does the earth's rotation effect windage, and, or, elevation?

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Considering earth is rotating at some 2400 MPH does this have any effect POI. I guess more appropiately asked, could it have an effect. In my simple minded reasoning, it seems this is plausable at least. I would think it could have an effect on either windage, elevation, or both, depending on which direction the bullet is being fired from? If the bullet was being fired from a non specific direction such as N.W. or S.E. and so on, I would think it would then effect both windage and elevation. But if the bullet is being fired from a perfect E.W.N.or S. direction, the effect should be one or the other.
Is there anyone out there who is a certified expert within this area of physics that would want to shed some light on the topic? And if so, would you be able to put it into perspective.
Without anyone having to say it, I'll openly admit this question is the result of a retired man, having too much time on his hands. But for those who respond, thanks for your time to answer my question.
 
just coriolis at long range. Not so much with windage, high pressure systems are anticyclonic due to coriolis but thats about as much as the coriolis effect plays on winds. For local wind effects though, earths rotations has no effect on them.
 
While obviously it is possible, I can't imagine anyone could blame a botched shot on the Coriolis effect. Over even a maximum shooting range the effect would by tiny and there's 100 different variables that could have more of an effect on a bullet than that. That's just my thinking though. I had heard of this before but it's hard to wrap my head around the Earth spinning. haha
 
Shooting artillery that stuff has to be worried about, but over even the longest ranges with rifles the wind and variations in it over 1000 to 2000 yards or meters would have much more effect. The wind and mirage would likely have so much effect that any other non-shooter, rifle, or ammunition effects would be lost in the noise.
 
So far as I am aware...

it is not necessary to consider the Coriolis effect in small arms firing - the effect is so small as to be insignificant. The only gun systems which need to take the effect into consideration are those firing at extreme ranges (e.g.: the Paris guns of WW1, which fired on Paris at ranges of ca. 75 miles). The flight times involved plus the fact that the trajectory rose to heights at which the atmospheric pressure was severely reduced made the effect of the Earth's rotation a significant consideration - and, even then, the best they could do was to hit the city, not any particular target or even specific part of the city. Perhaps if they had had some means of accurately reporting on the fall of the shot, they might have improved targeting.
And, FWIW, the Earth's rotational velocity is ca. 1,000 MPH at the equator.
PRD1 - mhb - Mike
 
GS,

For us more ordinary mortals such things are unimportant..........But if you're shooting extremely long ranges and that first shot hit is critical, or your having a target shoot with an Iowa class BB you've rented for the week then Coriolus Foce, latitude, compass direction and a host of other factors are important. Others I see have given you a starting point to answer your questions. You might want to visit the Fifty-Caliber Shooters Association, too..... >MW
 
And the Coriolis effect has an effect on weather. So the Earth's rotation has an indirect effect on windage... by affecting the wind.
 
I'm not so sure. Yes the Earth is rotating but so are we. Any shot fired would also be rotating at the same speed as the Earth. It's the same reason you can throw a ball straight up and it will fall back to you. Given there isn't any wind affecting the ball's trajectory.
 
browneu said:
I'm not so sure. Yes the Earth is rotating but so are we. Any shot fired would also be rotating at the same speed as the Earth. It's the same reason you can throw a ball straight up and it will fall back to you. Given there isn't any wind affecting the ball's trajectory.
Click to expand...
That only works for linear motion (the same reason if you jump on a speedboat, you dont crash into the steering column, yes I tried this when I was little) the Earth rotates, so we have angular motion. If I could draw a picture in 3d space I would, but I cant, and the wikipedia article on Coriolis effect is pretty good.
 
Coriolis effect should be max shooting north or south, nil shooting east or west. Only relevant for very long ranges (ie miles).
Imagine looking down on the earth from the north rotational pole, the earth would look like a disc, with the edge rotating at ~1000mph if a shooter shot north, towards the center of the "disc" the bullet would have an angular velocity of that 1000mph and would be moving toward parts of the earth with lower angular velocities (I think velocity would go down as the sine of latitude) so POI will be west of POA.
Again, only significant at long, long ranges.
 
I can't imagine anyone could blame a botched shot on the Coriolis effect
Click to expand...

oh HECK yeah, from now on I'm blaming EVERY botched shot on the Coriolis effect!

- well, unless I'm south of the Equator where bullets spin in the wrong direction.....
 
The old analog computers used for firing solutions on battleships had settings for the Coriolis effect. The Missouri class used these for the main guns until the ends of their service lives in the nineties. The Navy never found a reason to update them with digital electronics.

Rifles, even the extreme sniper variants, are still direct fire weapons, and don't really get into the ballistics variables of artillery. Segmented propellant charges anyone?
 
Yes Coriolis does affect at very long ranges like artillery but you will not see any of Coriolis affect at small arms ranges. What you will see at small arms ranges out past 800m is what is referred to as spin drift but that will only affect a shot a little bit at extreme long range shooting...important for snipers not so much for anyone else.

Spin drift is the result of the bullet rotating in one direction around the center axis of the bullet. The bullet will naturally begin to veer in the direction of the spin as the bullet travels. Spin drift is constant so it does affect your bullet at any range but unless you are shooting long ranges you will not notice any POI change. Because it is constant you will be able to figure out the spin drift of your rifle at any range and compensate for it. Barrels with fast twist rates have a higher degree of spin drift. Spin drift is still not nearly as important as wind drift however. If you can't call the wind, figuring out spin drift isn't going to help you because the adjustment for spin drift is directly subtracted from or added to your wind call.
 
I blamed it on a bad shot one time as a joke but my buddy didn't get it so it was lost in the moment, but at extreme long range the Coriolis effect is a know phenomenon in nature.
 
15" shells landing 26 miles away needed 3 days worth of 40 people figuring it out. than the 'difference' machine was developed and a shot could be figured by a dozen people in 6 hours. the machine was the size of 2, 3 room homes but it worked. that was WW ll.
besides earth moving and the angles involved, there was also the graduated changes in temperature and barometric pressure ascending and descending. .
today we have smart bombs and the cone of silence.
ain't technology wonderful?
 
Does that mean you should always shoot west to east for added velocity...
Click to expand...

If you fire east or west at long enough ranges the target will have moved with the rotation of the earth during the flight time.
 
The Isobars are too tight. Yeah, that's what threw me off. Caused by the Coriolis effect of course. :D
 
It sure does have an effect...
When I'm shooting westerly, the bullet just lands at the end of the barrel...
Easterly, I can shoot a .22lr over a thousand miles.
Sometimes when I jump really high, straight up, I land next door.:what:
YMMV.
p

I apologize for my sarcasm.
My misses are really my fault, not the coriolis effect.
 
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