Wind adjustments

[semtav]

Since this site has been so dead, thought I'd try to stir up a little discussion.

Subject being a quartering tailwind from the left and right.

We had a little bit of that going on at our long range match this weekend and I was hoping I would see a definite change in elevation to satisfy my curiosity. Unfortunately I didn't see enough difference to convince me .

I tried to shoot the 900 yd diamond without moving my sights just to see if I could see any differences. But when I drifted 2 off at 8:00 I had to move over and up a touch.

So does anyone see a right quartering tailwind push the bullet up and a left quartering tailwind push the bullet down?

[Castaway]

The left adjustment makes sense if shooting in a quartering wind. A tailwind will cause a higher bullet strike due to less wind resistance and higher retained velocity at distance. Something else is going on if your bullet strike was lower while shooting in a tail wind

[45-110]

Brian, Left or Right hand twist rifling?
kw

[semtav]

Right

[45-110]

Ruling out spin drift, it seems to me a right twist with a left wind would cause a downward spiral travel, but a right wind may cause bullet spiral climb? Hard to determine though if the wind was true horizontal level or a up draft or down.
Of course I could be all wrong!
kw

[semtav]

There are some charts that show a lower impact when one has a left quartering tailwind . Ive yet to see e a definitive result that showed that.

[semtav]

I probably shouldn't have mentioned anything about the 900 yd target. I think I've misled one into thinking those misses were what I was talking about. They weren't. They were the result of a right wind. Just wondering if anyone has a lot of experience shooting with switching tailwinds.

[Lead pot]

Brian,

Shooting at the Quigley since 2004 or 5 and the MT 1000 I sort of learned that that range gets some strange wind currents especially when the breeze comes 7-8 O-clock more over my left shoulder than at 9 O-clock for some reason shooting across the crick. And this also goes for the 1000. I don't know it the hill east of the road has the effect or what causes this.
When the wind direction is directly to the side, it can move a few degrees either way, and it won't change the size of the crosswind vector very much, but on the other hand, when a head or tail wind moves a few degrees to either side, you see a much larger change in the size of the crosswind vector. I think that this why a half-value wind occurs at 30 degrees, and not 45 degrees. This is a hard way for me to say that the wind deflection is more sensitive to changes in wind direction in a predominant head or tail wind than it is in a predominant crosswind.
I find if the wind is blowing hard left to right, that's going to deflect the bullet more than the same wind in my face for some reason at the Buffalo or stop sign.
The wind coming from the east there for me does not seem to effect changes as much with the same wind velocity

Watch those little yellow and white butter flys far down range and the dust in the direction they are flying compared to the winds you feel on the line. They tell you the truth. :D And if the wind is too strong watch the grass north of the crick LOL.

Kurt

[semtav]

Interesting observations Kurt.
One thing I did notice during the match was that the mirage was only appearing at the bottom of the scope near the low flat ground and not up by the targets at higher elevations.
I wonder how that all computes into sight adjustments.

The butterflies and dust were non existent this weekend 8-)

[Lead pot]

Give those little critters time. It will warm up. :D

I see that mirage do this even when it warms up there. I don't know it flat lines at the flats past the crick or not that I don't see it sometimes either.