Vertical deflection for crosswind.

[Tree]

Is it necessary to take this into consideration?

I have trued my balistic app out to 1000 but do I need to be concerned with what vertical deflection might have played a role in the actual vs calculated when truing?

 

[Lowlight]

Not unless the wind is over 12MPH in most cases. It can have an effect, but it's only dependent on Terrain around the target, and the velocity.

We zero out most CWJ, so you have to subtract that value, so the wind speeds have to go beyond it.

You will and can see it, but 90% of the time, it's unnecessary to worry about. The plates we shoot have a lot of vertical, they are taller vs their width. So they can absorb the small errors we see with CWJ.

Dont sweat it, just because you read it on the internet and guys throw a metric ton of numbers at you, doesn't mean it is practical or correct.

Oh, and before the Book Club of the month readers come on an say, But, But, I doped the Valkyrie with an 88gr Bullet before the Guardian Match in an 18 to 24MPH here in CO, traveled to TN with less than 6 MPH. My data was .2 off at 800 yards elevation with a .224 getting blown in the wind much worse than your typical 6.5 you saw people shooting. I dropped a .1 during the match from my data and was 12th with a mouse gun wearing heels.

 

[Deleted member 113831]

The vertical deflection is usually about 10% of drift. That lines up perfectly with @Lowlight 's experience. The drift differential he experienced was about 2.4mils between zeroing conditions and match conditions. So, 0.2mils is right in that 10% of drift range.

 

[lte82]

The take away I got from the equations written by guys smarter than me, and the reason why it sometimes seems to have an effect while other times it doesn't, is that CWJ is really an absolute value (like inches, or mm) not relative or based on an angle value (like moa or mil), and the closer the crosswind is to your muzzle the more effect CJW has on your solution. If your bullet jumps 3mm vertical within the first 5 cm of leaving your barrel because the wind is present at your muzzle, the deflection or change of POI on target is greater than if your bullet jumps 3mm vertical at say 10m away because you were shooting from a sheltered position.

 

[Lowlight]

as noted I find you need a true 12MPH + before it shows up

So just like @Skookum says, 10% of your wind difference between conditions. The error has to grow like angles.

If you zero at 6 and shoot in 12, you don't really see it, if you zero at 6 and shoot at 18 you start too.

The yadda, yadda of the books is just overexplaining something we zero out most of the time.

Don't sweat the small stuff, your personal error factor as a new shooter is certainly bigger. When you start shooting 1/2 MOA groups consistently at distance, then you can consider these outside effects. Plus with Gusts and Lulls, it's never consistent because the wind is not consistent. Would be like chasing your tail for every shot.

 

[Tree]

Thanks guys. Will ignore for now till I get significantly better. ?

 

[Kobyashi72]

Is it necessary to take this into consideration?

I have trued my balistic app out to 1000 but do I need to be concerned with what vertical deflection might have played a role in the actual vs calculated when truing?

Did you true it with the azimuth and latitude set?

 

[Squat]

Don't sweat the small stuff, your personal error factor as a new shooter is certainly bigger. When you start shooting 1/2 MOA groups consistently at distance, then you can consider these outside effects. Plus with Gusts and Lulls, it's never consistent because the wind is not consistent. Would be like chasing your tail for every shot.

I always remember this when i start to worry about minutiae. When i am good enough to call wind to the .5 mph then i can worry about the .1 mil i am off due to other factors.

 

[DeftSystems]

It's a cool question to think about. Some of the other posters have alluded to the fact that this is a really difficult effect to chase down due to its small magnitude. At 1000m, there are many effects which eclipse it, not the least of which is actually ensuring a uniform windspeed across a click. Happy hunting.