Coriolis Effect

John: Yes (assuming you have everything else in your ballistics worked out).

Word of advice - if you use 4000NV, after you input all atmospherical data into the software, you might want to leave Kestrel's screen on DALT (density altitude) and occasionally verify it (change in DALT will give you indication of sudden atmospherical change - it can be rapidly changing baro pressure, temperature rise/drop, etc.). And even that is not always visible - you may get the same DALT reading when humidity change offsets slight baro pressure change, etc. and one might not notice that the ballistic solution should be re-calculated. And you probably already know that for real surgical ELR precision there's a ton of other variables as well, all the way from barrel temperature to the actual temperature of the round you are chambering, etc., but most of these cause minimal differences that one often cannot correct with coarse/tactical 0.1 mil clicks.

However, in my experience the most common cause of misses in ELR is error in wind estimation, and spindrift and coriolis effect (better said - lack of compensating for them) is usually attributed to this as well.

Bottom line - to finally shut my mouth since I'm probably preaching to the choir, ELR is about perfection, but even if you do have perfectly worked out ballistics (banding/trueing and compensating for all variables), you have perfect shooting/trigger execution, you are using perfect rifle and perfectly reloaded ammo, etc. there is still a small portion of 'shooter's luck' involved. We can get very close, but math/physics/sensors/technology/doppler and actual empirical data etc. all only go so far, and until we'll all switch to laser-guided bullets (or at least will have access to cheap multiple-laser-atmo-scanning devices able to monitor and 'predict' the wind conditions along the complete bullet flight), until then we'll never be able to compute ballistic solution that would work 100% time, and perhaps not even then... :rolleyes:

Sorry for my long post again, good luck and shoot safe :)


Gun_Slinger

Yes your Right, I do ok behind the trigger But these Apps are driving me crazy because I am getting 3 differant solutions
and only one matches my range finder the Strelok free version and the Strelok+ matches my LRF but this new Strelok Pro does not and its numbers are a bit on the wild side

Strelok+ Says @ 2000yds= 408.8fps, 55.7ftlbs, and a drop of4262.08"inches, ( @ 881yds = 27.1 moa )

Strelok Pro says @2000yds= 818.5fps, 223ftlbs and a drop of 2973.23" inches, ( @ 881yds = 26.29 moa )

And my Bushnell G-Force 1300 ARC says ( @ 881yds = 27.1 moa )

This is based on a .270 150gr, BC of .480 at 2828, @ 29.92inhg, 59deg F, AT 0 Alt as per sighting in weather

so something is seriously wrong somewhere??? and I just cant figure it out so I think what I will do is use the Plus version and Add or Subtract from the final Solutions as you said because your formula is right its just my App that is Letting the side down.

Thanks Mate,

John
 
Spend $400.+ and get a Horus/Kestrel meter & ballistics computer. It's ALL figured out for you with that unit (except for distance.) Load in your ballistics, calibrate the compass, enter the distance. Then with the H/K meter get wind and target direction (and angle, if any) and it gives you the firing solution, the complete firing solution.

Coroilis effect will affect you Most markedly shooting directly north to south and the reverse. And it is most noticable beyond 1,500 meters/yards. As your compass direction of firing moves away from the lines of longitude and more parallel with lines of latitude the corolis effect lessens.

The rotation of the earth causes this effect. i.e. your target moves DURING the bullet flight (right when shooting south, left when shooting north)
and when the bullet lands the target is not in the same place it was when the bullet left the barrel.
 
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Spend $400.+ and get a Horus/Kestrel meter & ballistics computer. It's ALL figured out for you with that unit (except for distance.) Load in your ballistics, calibrate the compass, enter the distance. Then with the H/K meter get wind and target direction (and angle, if any) and it gives you the firing solution, the complete firing solution.

Coroilis effect will affect you Most markedly shooting directly north to south and the reverse. And it is most noticable beyond 1,500 meters/yards. As your compass direction of firing moves away from the lines of longitude and more parallel with lines of latitude the corolis effect lessens.

The rotation of the earth causes this effect. i.e. your target moves DURING the bullet flight (right when shooting south, left when shooting north)
and when the bullet lands the target is not in the same place it was when the bullet left the barrel.

That Horus with BT over here is more than twice that Price and the AP model isnt even over here,

In the last section you say about how the target/bullet move left or right but others have said it does'nt but I believe you are right because the bullet is no longer attached to the earth when it leaves the muzzle.

Thanks for clearing that up for me.

John
 
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Was thinking about this thing the other day. Decided to mathematically see it it something to worry about at 1000 yards.

I have accounted for spin in the past. It is ~7 inches right for my load on a standard day.

Cor is 2.7 inches right at my latitude on a standard day.

Eotvos is + 2.5 inches due east and - 2.5 inches due west.

Now at 1500 yards it gets exponentially worse.

Spin = 21.5 inches
Cor = 7.4 inches
Eot = + 8.3 inches due east

Given, my little 270 is just barely supersonic at 1500, but if I can calculate the variable, I might just have to try it.
 
Hmmm... Since you insist on reviving a dead Thread with bogus information, maybe it's time for me to mention that was has been discussed so far isn't even accurately called the Coriolis Effect.

G'day Mate about time you showed up, I think he is a might confused, But it is a topic that is easily forgotten Or mixed up with you know what,

John
 
Who ever says other wise has watched Shooter one to many times or has never stretched out that far.


lolol - well stated.

hell, i just look at my dust cloud and then compensate.
it's not like i'm going to HAVE TO make a first hit to take out a threat or anything. hahahahaha
wind and vertical spread and not timing my heartbeat dominate my error anyways
 
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