Spin Drift and Coriolis: How Much Do They Really Matter?

[FURMAN]

Read the article here:

Spin Drift and Coriolis: How Much Do They Really Matter? - Long Range Only

Spin Drift and Coriolis: How Much Do They Really Matter? Both can move the center of impact enough to matter at long range. The …

www.longrangeonly.com

I think a lot of us have that been doing this for a long time take some things for granted. Newer shooters may not have a good understanding of this or how it affects them. It also does reinforce why we need some of the newer electronics that we use to be as precise as we possibly can.

Discuss here:

 

[windypants]

If I were to only shoot my long range rifle at elk out to say, 800 yards, I could probably get away with ignoring spin drift and coriolis. But long range coyote hunting, where I have a vital zone of only 5” at best, has taught me that I have to take it into account. A 2 mph breeze will double or cancel spin drift, depending on the direction. And that is enough to miss a coyote at midrange. When I’m setting up for a midrange shot, a breeze on my right cheek means a zero windage hold, and on my left cheek is a minimum of 1.0 left MOA. I can make that shot fairly quickly, but more wind and/or distance requires more time and deliberation to get the calculations right. Shooting in the wind obviously requires a lot of thought to go into the shot. Shooting at a small target at long range has shown me how much difference that subtle breeze makes when compounded by spin drift.

I do ignore coriolis and just let the ballistic solver take care of that for me. The Revic app seems to be catty enough to do a good job of that. That would sure complicate things if I had to calculate that in my head for every long range shot. Does anybody else think about coriolis?

 

[Mark Dille]

Both are important, as is aero jump, depending on wind direction relative to the direction of the shot. That is why I always try and enter the wind vector and magnitude in my Fury 5000s instead of a generic right/left crosswind. It will account for aero jump accordingly.

 

[FURMAN]

Both are important, as is aero jump, depending on wind direction relative to the direction of the shot. That is why I always try and enter the wind vector and magnitude in my Fury 5000s instead of a generic right/left crosswind. It will account for aero jump accordingly.

I’ll be doing a separate article on aero jump. It was just too much for one article.

 

[scottrod338]

I always put in spin drift and shot angle on all my shots, even at close range just to develop a habit of doing it. I will generally enter coriolis when I get to and past 1000yds.
The charts in the article definitely tell the story. Great information.
I think Gunwerks put out a video a while ago with a demonstration shooting same dial up north south east and west to show the affect

 

[FURMAN]

I always put in spin drift and shot angle on all my shots, even at close range just to develop a habit of doing it. I will generally enter coriolis when I get to and past 1000yds.
The charts in the article definitely tell the story. Great information.
I think Gunwerks put out a video a while ago with a demonstration shooting same dial up north south east and west to show the affect

Yes, they did. The one I am thinking of may have been ten years ago. Man, I am getting old.

 

[Willys]

Spindrift + Corialis is 7” right at 1000 yards. Corialis is +\- 2.4” high/low shooting east/west. If zero wind I dial .5 moa left to compensate. If wind I use rf outputted moa. I ignore Corialis impact on vertical. This with 300 gr Berger Lapua Ai