Wind Drift??

[Bob-WY]

Out pronghorn hunting yesterday and the wind kicked up. end results: I over-thought a shot and missed, wife didn't try to dope the wind and dead critter, but a bit of bullet drift.

How much do you allow for wind on a 20 MPH cross breeze? How far out do you start to see effects? How much?

 

[MTLabrador]

The Hornady ballistics calculator app is handy for wind. 20 mph is a lot of wind at any real distance.

 

[ImBillT]

Too much missing information to get specific. It depends primarily on bullet, muzzle velocity and the angle of the wind, then slightly on a lot of other things.

Generally for hunting in the wind, if it doesn’t feel super windy(probably 10mph or less), then it isn’t windy enough to matter a whole lot inside 300yds, and even to 500yds, just aim at the windy side of the target zone. That means that if your target zone on that animal is 8” wide and the wind is coming from the right, then aim on the right side of that 8” zone, but don’t come off the zone.

When it feels super windy, you either need to really know what your doing OR keep shots inside 300yds, keep your crosshairs on the target zone of the animal, but on the side the wind is coming from. BETTER YET, if possible, change position so that instead having a direct crosswind, you have a direct tailwind or direct headwind. If you cant get a direct headwind or tailwind, then even reducing the angle of the wind, will reduce the amount of bullet drift. There are charts for how much “value” to give a wind depending on its angle, and how to estimate low to medium wind speeds based on leaves, grass, trees etc. if you want to dive down the rabbit hole.

Below is a chart of wind drift based on a .257” 115gr bullet launched at 3200fps. You’ll have to click it to see the wind numbers, but you’ll see that even in 20mph out to 300yds, simply aiming on the windy edge of the target zone is suitable for medium to large game. On a pronghorn you might be pushing it if you didn’t have the experience and confidence to hold 5” past your target zone. By 400yds it’s obvious that you need to know what your wind speed, angle, and distance to the target actually are, as being off on any of those is beginning to make a significant difference. A rangefinder is only a small part of the equation here.

 

[MinnesotaHunter]

On average of common hunting calibers 20MPH will push your bullet between 4-5" at 200yds, and that will a little more than double at 300. I linked a decent article below.

https://www.backcountrychronicles.com/wind-drift-missed-shot/

 

[ImBillT]

The Hornady ballistics calculator app is handy for wind. 20 mph is a lot of wind at any real distance.

My guess is that 20mph is also a guess. Was it 18mph? 24mph? Past 300yds, that’s in a zone where you really need to know what you’re doing and be really good at it, OR get a headwind or tailwind.

 

[WyoDoug]

Alot goes into that, everything from temperature, bullet weight, wind direction and velocity compared to bullet direction, was shot straight line or from elevation, powder load, etc. Way too many variables to consider and not enough information given to be specific. All that has to be considered in the equation for the answer to your question to be valid.

 

[Bob-WY]

I knew this wouldn't be a simple answer

We stay inside 200 yards on all shots, on all animals, UNLESS ideal conditions and then we'd max out at 300.

So from charts and the article above, given our limits of 200 (guns are .30-06 and 7mm08) we are looking at roughly 4-5 inch drift in a 20MPH cross wind..

Using those numbers yesterdays shots make sense, I played to much wind and wife aimed dead on and drifted about 4-5 inches from 196 yds. Me, I just brain farted and missed. I think my main lesson learned is never put the cross hairs outside the kill zone, if I feel I need to, change the shot conditions in one way or another.

 

[Doublecluck]

About this much… for my 7rm.. with my bullet, and elevation, and etc. get a app or if your shots are only 200 just aim center of lung unless your in a hurricane.