Coriolis Effect...So confusing....

[Lavid2002]

Im learning so much about shooting so fast its hard to remember all of it. I am the first shooter in my family and a young one at that. I find it helpfull if things are re-worded so I can understand them if I want o remember them.....so....heres what I understand so far. The Corilois effect can have great effects at extended distances. Veering bullets off their zero(Assuming no ind and no corilois effect) by roughly ten inches at one mile if shooting due north.
*Corilois effect IS real in the shooting sports, and marksmen shooting at extended ranges often use electrical compases and formulas to determin the effect....I certainly was used for the shot taken with the mcmillan tac50 for the guy out at 2,410M

Please teach me a litte more. I know a TAD more than this BUT I have to leave for school.
Thanks!
Dave

 

[Old Timer]

There is a common misconception regarding the Coriolis effect on target shooting. The facts are that, at the range we shoot, the Coriolis effect is irrelevant. In ballistics only the trajectories of very long-range artillery shells would be affected. Something like the huge railway gun used by Germany against France in World War I which had a range of about 75 miles. At ranges less than about 50 miles the Coriolis effect becomes irrelevant.

However, there may be a slight application of the Eötvös effect for extremely high velocity rounds fired in an east to west or west to east direction which would cause the eastward fired round to deflect slightly upward, and thus act as if it were lighter, and the westward fired round to deflect slightly downward, and thus act as if it were heavier. However, again, at the short range most of us shoot even the Eötvös effect would be largely irrelevant.

The only commonly observable result of the Coriolis effect is on our weather. Hurricanes are Coriolis machines powered by heat stored in the oceans near the equator.

 

[mikejonestkd]

The impact on long range shooting is very minor, it really comes into play for artillery rounds and ranges measured in miles, not for bullets and ranges measures in yards. I'd spend more time trying to dope the wind and guesstimate bullet drop than worry about the Coriolis effect.

Long range target shooters ( 1000 yards or so ) usually get to take sighters first before they shoot for score. they can make any minor adjustments then.

 

[OnTheFly]

Agree with mikejonestkd and Old Timer. Coriolis effect is minimal at short distances especially when we are talking about a relatively fast moving object. If you are talking about a slow object moving a shorter distance or a fast object traveling a long distance, Coriolis effect will be greater.

Fly

 

[schmellba99]

At distances of a mile or greater, you generally have to account for the Coriolis effect.

Basically you are leading the target the distance that it is moving via the rotation of the earth for the time span the projectile is in the air. We are all moving at roughly 2000 mph from west to east at all times.

Depending on your location on the earth and the angle you are shooting compared to the axis, the effect will be greater or less for the same distance.

It has more to do with artillery than anything, but shooting at distances in the 1 mile + range generally have to have this taken into account to be accurate.

 

[Redneckrepairs]

Its nothing to worry about unless and until you are shooting " for score " beyond 1k range . Until then just dont worry about it , much like you dont worry about what angle the valves and valve seats are cut to in the motor of the car you drive . At your power level ( in either case ) it simply does not matter , and if you reach a level where it does you will by then have an idea about the differences and effects.

 

[Bud Helms]

The facts are that, at the range we shoot, the Coriolis effect is irrelevant. In ballistics only the trajectories of very long-range artillery shells would be affected. Something like the huge railway gun used by Germany against France in World War I which had a range of about 75 miles. At ranges less than about 50 miles the Coriolis effect becomes irrelevant.

The impact on long range shooting is very minor, it really comes into play for artillery rounds and ranges measured in miles, not for bullets and ranges measures in yards.

Coriolis effect is minimal at short distances ...

It has more to do with artillery than anything, but shooting at distances in the 1 mile + range generally have to have this taken into account to be accurate.

Okay guys, there are some variations in the contributions here, but I think we're getting the point.

 

[MeekAndMild]

But what about relativity, Bud? There's a lot of discussion on some boards about the risk of a bullet imploding to form a black hole. I've actually seen this on some of my targets.

 

[Heretic]

Physics Allert

Warning, Warning This post contains Physics and Math. Some people are offended by math. If you are one of those go on to the next thread now or, read only at bedtime, as drowsiness is a known side effect of Physics

If you stand on the Equator you have a velocity of about 1000 MPH [earth circumference of 24000 miles divided by 24 hours]. At the poles the speed is zero. The speed at 40 degrees N or S is about 600 MPH. As you get closer to the poles the speed drops.

Fun experiment:
Need one playground marry-go-round, several beanbags or tennis balls [nothing hard], a friend who will agree to do something weird [Children do well on this].
Place yourself and your friend on opposite sides of the marry-go-round with the balls. Start the marry-go-round spinning [not too fast]. Once you are both on, try to play catch across the center of the spinning platform. It is interesting to see the apparent path of the ball.

The following is based on Latitude 39.89345 N, which happens to be the latitude of my home. If I were to shoot at a target one mile north, at 39.90162 N, There would be a difference in rotational speed of about 2 inches per second. If the flight time of the bullet were three seconds, the impact would be about 6 inches to the right of the point of aim. [Shooting south the impact would be left.] Since this is substantially less than the vaunted minute of angle standard, the chances are that other factors will produce a greater effect.

For rifles you could pretty much ignore this since the range is relatively short. Now if you are engaged in long-range artillery duels or lobbing ballistics missiles, you might want to include it in your calculations.

Oh, by the way, the Coriolis effect has nothing to do with which way your toilet swirls in a flush.

 

[Lavid2002]

? Evotos effect...

There is a common misconception regarding the Coriolis effect on target shooting. The facts are that, at the range we shoot, the Coriolis effect is irrelevant. In ballistics only the trajectories of very long-range artillery shells would be affected. Something like the huge railway gun used by Germany against France in World War I which had a range of about 75 miles. At ranges less than about 50 miles the Coriolis effect becomes irrelevant.

However, there may be a slight application of the Eötvös effect for extremely high velocity rounds fired in an east to west or west to east direction which would cause the eastward fired round to deflect slightly upward, and thus act as if it were lighter, and the westward fired round to deflect slightly downward, and thus act as if it were heavier. However, again, at the short range most of us shoot even the Eötvös effect would be largely irrelevant.

The only commonly observable result of the Coriolis effect is on our weather. Hurricanes are Coriolis machines powered by heat stored in the oceans near the equator.

Act as if it were lighter or heavier? Bullet weight doesn' t determine drop. Gravity acts the same on all objects despite weight at the same speed.

 

[TimRB]

FWIW, here's an interesting video demonstrating the Coriolis effect by way of kids rolling balls on the surface of a playground merry-go-round. If they spun the merry-go-round the other way, it would show how the bullets of northern hemisphere shooters turn to the right (a *little* bit).

http://www.youtube.com/watch?v=_36MiCUS1ro

Tim

 

[Wuchak]

Gravity acts the same on all objects despite weight at the same speed

Not exactly.

http://en.wikipedia.org/wiki/E%C3%B6tv%C3%B6s_effect

 

[Lavid2002]

The statement was, "treating the bullet as if it was lighter"
I am not doubting the eotvos effect, im stating that all objects drop at the same speed despite weight (not condifering air resistance or wind etc...) Mind you the evotos effect will change how it drops, gravity stil acts the same on the object. I was countering a comparison, not the statement.

 

[Wildalaska]

Oh, by the way, the Coriolis effect has nothing to do with which way your toilet swirls in a flush.

Great..... so I have wasted the past 40 years of my life staring into toilets and making notes about something that doesnt exist.

Thanks a lot

WildyouhavedestroyedmyreasonforbeingAlaska TM