Help understanding windage calculation.

[Nsghunter]

I have been reading some the last few days about terminal ballistics, bullet construction and shot placement. Today I was reading about the effects of ballistic coefficient and wind adjustments for shot placement.

"...a 10-m.p.h. crosswind drifts the projectile 7.0 inches off course at 300 yards, 13.1 inches at 400 yards and 21.4 inches at 500 yards..." taken from http://www.americanrifleman.org/article ... dvantages/

Does this mean that I would need to aim 21.4 inches opposite from the direction of the wind on the target 500 yards away? Therefore I would need to generate an imaginary measurement on the beast that was 21.4 inches off the lethal poa?

I couldn't think of a better way to ask the question.

I always chuckle at theses types of questions. I am asking about taking shots 200 yards greater than I can ever see in my area and imagining taking them on game I may never get a chance to hunt. I guess if I ever get to go west and bag a big one I'll be prepared.

 

[Jcalder]

Obviously projectile and velocity play a big part in wind drift. Ballistic coefficient is another talking point. But to simply answer your question in the scenario above you are correct. You would need to hold 21.4 inches opposite the wind.


Big or small, kill em all

 

[TNRifleman]

Obviously projectile and velocity play a big part in wind drift. Ballistic coefficient is another talking point. But to simply answer your question in the scenario above you are correct. You would need to hold 21.4 inches opposite the wind.


Big or small, kill em all

Yes and remember that article is addressing a specific bullet in a specific weight. If you shoot a different bullet or different weight of the same bullet type, your windage adjustment could be much different.

 

[Nsghunter]

Obviously projectile and velocity play a big part in wind drift. Ballistic coefficient is another talking point. But to simply answer your question in the scenario above you are correct. You would need to hold 21.4 inches opposite the wind.


Big or small, kill em all

Thanks,

 

[Nsghunter]

Obviously projectile and velocity play a big part in wind drift. Ballistic coefficient is another talking point. But to simply answer your question in the scenario above you are correct. You would need to hold 21.4 inches opposite the wind.


Big or small, kill em all

Yes and remember that article is addressing a specific bullet in a specific weight. If you shoot a different bullet or different weight of the same bullet type, your windage adjustment could be much different.

I appreciate the clarity. I thought after I found my exact load I would calculate the windage and then keep it in mind when I shoot.

 

[280longshot]

I wouldn't worry to much about it but yes educate yourself about wind drift, and if possible practice at your intended yardage.
You may have other issues to contend with at 500 yrds especially with a hunting rifle.
Shooting a hunting rifle from a rest is not even in comparison with a target rifle at a bench on sand bags.

Sent from my SM-G900V using Tapatalk

 

[mr.big]

wind is tricky for sure,,,shooting at deer at 300 yards you should be good to hold center and shoot unless it is a sure enough tornado,,at 500 yards a 10 mph wind could cause some bad things to happen,,if I was taking that shot I would have practiced it enough to know where in my scope 4 MOA is at or I would just dial in 4 MOA,,

 

[Nsghunter]

Thanks for the info guys. As above stated before I took a five hundred yard shot there would have to be many things addressed about my shooting. The question was close to rhetorical but not entirely.

 

[fairchaser]

That would be correct for a full wind value. Any half or quartering wind would have lesser effect. On long shots, often wind will affect poi more than trajectory especially over 15 mph. Estimating is almost impossible unless it can be dialed in or measured using mildots.