collapse
For when you only get one shot! FREE SHIPPING ON ORDERS OVER $99.00!

Author Topic: Simple adjustment for wind drift ?  (Read 2628 times)

Offline Magnum_Willys

  • Trade Count: (+1)
  • Frontiersman
  • *****
  • Join Date: Nov 2009
  • Posts: 2851
Simple adjustment for wind drift ?
« on: April 06, 2017, 12:43:06 PM »
Have seen guys prefer Mil scopes for wind drift correction as the mils correlate better for adjustments?  Played around with Hornady Ballistic calculator to see what I could do with my moa scope for quick and dirty estimate to double check more sophisticated methods.

Turns out that just one click for every 100 yards after the first 100 is perfect for a 10 mph wind with my setup.  Can it be this easy ?  ( yea I know elevation/weather conditions will change things but probably not more than my wind estimates ?)

i.e. - 600 yards turn 5 clicks to adjust for 10mph cross wind. 



      

Offline kentrek

  • Virtual Campfire
  • Trade Count: (0)
  • Frontiersman
  • *
  • Join Date: Mar 2012
  • Posts: 2940
  • Location: west coast
Re: Simple adjustment for wind drift ?
« Reply #1 on: April 06, 2017, 01:05:45 PM »
It'd be that easy if you only ever had a perfect 10 mph wind  :chuckle:

Online Bob33

  • Global Moderator
  • Trade Count: (+2)
  • Explorer
  • *****
  • Join Date: Apr 2009
  • Posts: 17273
  • Groups: SCI, RMEF, NRA
Re: Simple adjustment for wind drift ?
« Reply #2 on: April 06, 2017, 01:15:19 PM »
If the drift values are in inches, they look low to me.
Nature. It's cheaper than therapy.

Offline Magnum_Willys

  • Trade Count: (+1)
  • Frontiersman
  • *****
  • Join Date: Nov 2009
  • Posts: 2851
Re: Simple adjustment for wind drift ?
« Reply #3 on: April 06, 2017, 01:55:02 PM »
If the drift values are in inches, they look low to me.

Thank you Bob ! You are right, I had selected G7 in the calculator instead of G1.  arghhh

Doesn't look near as sexy when you put the right numbers in  :bash:

« Last Edit: April 06, 2017, 03:00:16 PM by Magnum_Willys »

Offline Yondering

  • Off-Topics
  • Trade Count: (+1)
  • Scout
  • *
  • Join Date: Sep 2013
  • Posts: 303
  • Location: Sedro Woolley
Re: Simple adjustment for wind drift ?
« Reply #4 on: April 06, 2017, 05:48:31 PM »
If the drift values are in inches, they look low to me.

Thank you Bob ! You are right, I had selected G7 in the calculator instead of G1.  arghhh

Doesn't look near as sexy when you put the right numbers in  :bash:

If you play with the wind values, you can find a specific wind speed for your load and location that works with what you're trying to do out to 600-800 yards. Beyond that the wind drift starts to decay more and you'll have to add more correction.

I forget what it's called, but this is a technique some precision shooters use. For example, if I know my load needs 1 click per hundred yards in a 3 mph wind, I can factor that by the actual wind reading to easily get a quick wind dope. Say it's 400 yards and a 9mph wind, I'll need 12 clicks.

This is approximate of course, but can be close enough in the medium distances to work well.

Online Reidus

  • Trade Count: (+6)
  • Longhunter
  • *****
  • Join Date: Oct 2013
  • Posts: 650
  • Location: Tri-Cities
Re: Simple adjustment for wind drift ?
« Reply #5 on: April 06, 2017, 06:32:06 PM »
Put the data in excel and make a graph. Add a line of best fit and see if excel can come up with an equation. Maybe you can dumb the equation down to something simple.


Offline Yondering

  • Off-Topics
  • Trade Count: (+1)
  • Scout
  • *
  • Join Date: Sep 2013
  • Posts: 303
  • Location: Sedro Woolley
Re: Simple adjustment for wind drift ?
« Reply #6 on: April 07, 2017, 09:53:36 AM »
No need to use excel, just play with wind values in your ballistics app.

Magnum_Willys - I made some assumptions about your load and environmentals, but this should work as an example of what I'm talking about. I used: .338 300gr SMK @ 2850fps, G7 .3824, 330ft altitude, 50* F, 30.0586 in. HG.

Experimenting with wind values, 6 mph wind predicts 1 click (1/4 MOA) out to ~600 yards. Past that you need more clicks, 800 yards needs 9 clicks for example.

If all that is correct and proves out in the field, make yourself a chart based on 1 click /100 and 6 mph wind. Then any actual wind calculations are a factor of that value; 9mph wind for example will be 1.5 clicks /100.

Hope that helps!

Online Reidus

  • Trade Count: (+6)
  • Longhunter
  • *****
  • Join Date: Oct 2013
  • Posts: 650
  • Location: Tri-Cities
Re: Simple adjustment for wind drift ?
« Reply #7 on: April 07, 2017, 07:37:03 PM »
Here's an image that shows what wind drift looks like in a 10mph crosswind. All calibers/bullets will have a similar curve.

http://www.accurateshooter.com/cartridge-guides/243win/

Edit: the chart refers to drift in inches rather than MOA which is what you're using to dial your scope so I believe that would make the curve flatter.
« Last Edit: April 07, 2017, 07:42:36 PM by Reidus »

Offline Stein

  • Trade Count: (+1)
  • Frontiersman
  • *****
  • Join Date: Sep 2013
  • Posts: 3282
Re: Simple adjustment for wind drift ?
« Reply #8 on: April 07, 2017, 07:40:18 PM »
Yeah, it isn't the clicking that is hard, it is the precision estimating of wind over long complex terrain that is the challenge.  Whip your phone out of your pocket and in four seconds you have the exact calculations done.

Online Reidus

  • Trade Count: (+6)
  • Longhunter
  • *****
  • Join Date: Oct 2013
  • Posts: 650
  • Location: Tri-Cities
Re: Simple adjustment for wind drift ?
« Reply #9 on: April 07, 2017, 07:46:13 PM »
Or just go with the a zeiss rapid z reticle( Or something similar) that has the hash marks for 10mph wind at each yardage.

Offline SilkOnTheWetSide

  • Virtual Campfire
  • Trade Count: (+1)
  • Sourdough
  • *
  • Join Date: Jun 2011
  • Posts: 1249
  • Location: Enumclaw
Simple adjustment for wind drift ?
« Reply #10 on: April 07, 2017, 07:47:49 PM »
Here's an image that shows what wind drift looks like in a 10mph crosswind. All calibers/bullets will have a similar curve.

http://www.accurateshooter.com/cartridge-guides/243win/

Edit: the chart refers to drift in inches rather than MOA which is what you're using to dial your scope so I believe that would make the curve flatter.

Man that's some crazy drift!

My 28 only drifts 44" @ 1000 yards. Just over a MIL.

Also, IMO you should hold for wind, not dial...


Sent from my iPhone using Tapatalk

Offline Magnum_Willys

  • Trade Count: (+1)
  • Frontiersman
  • *****
  • Join Date: Nov 2009
  • Posts: 2851
Re: Simple adjustment for wind drift ?
« Reply #11 on: April 20, 2017, 08:33:33 AM »
No need to use excel, just play with wind values in your ballistics app.

Magnum_Willys - I made some assumptions about your load and environmentals, but this should work as an example of what I'm talking about. I used: .338 300gr SMK @ 2850fps, G7 .3824, 330ft altitude, 50* F, 30.0586 in. HG.

Experimenting with wind values, 6 mph wind predicts 1 click (1/4 MOA) out to ~600 yards. Past that you need more clicks, 800 yards needs 9 clicks for example.

If all that is correct and proves out in the field, make yourself a chart based on 1 click /100 and 6 mph wind. Then any actual wind calculations are a factor of that value; 9mph wind for example will be 1.5 clicks /100.

Hope that helps!


Good idea, i didnt think of using wind multiples other than 10mph. That opens up some possibilities.   

Offline Bill W

  • Trade Count: (0)
  • Sourdough
  • *****
  • Join Date: Sep 2013
  • Posts: 1425
  • Location: Moses Lake
  • Groups: NRA, CBA
Re: Simple adjustment for wind drift ?
« Reply #12 on: April 20, 2017, 09:06:56 AM »
Better have your windage turret marked for the actual zero.  Otherwise you won't be able to tell what the "non wind" zero is.    My personal preference now is holding off for wind.  I was shooting in my first nationals in 2006 and I had the windage built into my sight corrections so I could hold closer to the x ring.   The wind was approximately 20 mph and then it reversed.   I went to the sighter to see what my new zero was and the combination of the new wind direction and the correction in my scope "blew" the bullet off the target.   I had an eventful couple of minutes until the wind came back to the original direction.

Offline Magnum_Willys

  • Trade Count: (+1)
  • Frontiersman
  • *****
  • Join Date: Nov 2009
  • Posts: 2851
Re: Simple adjustment for wind drift ?
« Reply #13 on: April 20, 2017, 09:22:05 AM »
Yea my inclination would be to dial close and hold for small variations. I can see how a big change would mess you up!

Offline high country

  • Trade Count: (0)
  • Old Salt
  • ******
  • Join Date: May 2007
  • Posts: 5130
Re: Simple adjustment for wind drift ?
« Reply #14 on: April 21, 2017, 08:23:12 AM »
Better have your windage turret marked for the actual zero.  Otherwise you won't be able to tell what the "non wind" zero is.    My personal preference now is holding off for wind.  I was shooting in my first nationals in 2006 and I had the windage built into my sight corrections so I could hold closer to the x ring.   The wind was approximately 20 mph and then it reversed.   I went to the sighter to see what my new zero was and the combination of the new wind direction and the correction in my scope "blew" the bullet off the target.   I had an eventful couple of minutes until the wind came back to the original direction.

Agreed. I got burned by a failure to RTZ on the windage too. Now I'm straight up hold for wind. If I need more than a mil or two......I need to reposition due to my own ethics.

 

* Recent Topics

Thoughts on a 7mm wsm by CaNINE
[Today at 08:42:24 AM]


Rimrock by Southpole
[Today at 08:42:02 AM]


Who drew by fisheral87
[Today at 08:40:59 AM]


Crawdad Mania - 2018 by Shrimper
[Today at 08:39:07 AM]


Teanaway archery elk by ridgefire
[Today at 08:38:41 AM]


Mt. View Unit by WapitiTalk1
[Today at 08:37:43 AM]


The daily struggle by eburgtrapper
[Today at 08:35:59 AM]


Wdfw drawing fiasco explanation by trophyhunt
[Today at 08:23:00 AM]


Peaches by teanawayslayer
[Today at 08:22:25 AM]


House by Ellensburg for sale by C-Money
[Today at 08:22:18 AM]


Observatory Archery Quality Elk by eastfork
[Today at 07:53:38 AM]


Idaho results by hunter-4-life
[Today at 07:50:40 AM]


Coweman cow by Jharstad7182
[Today at 07:39:35 AM]


Anybody have a Kimber Hunter in 6.5 Creed? by Southpole
[Today at 07:36:23 AM]


2018 Special Permits: Drawing Results by Mr Mykiss
[Today at 07:34:25 AM]


Budget friendly spotter by JWBINX
[Today at 07:30:13 AM]


WTB spotting scope by WSU
[Today at 07:19:48 AM]


WTB: 10/22 TRIGGER GOUP by Special T
[Today at 07:17:45 AM]


Colockum spike or cow? POLL by stickslinger
[Today at 06:54:22 AM]


Permits by White Pass Outfitters
[Today at 06:36:44 AM]