Where can I read up windage and mirage?

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Solar

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Well, just got up to 200 yd and 300 yd, the rifle can shoot sub MOA (around 0.6 to 0.8 MOA). However, the wind in southern AB is causing problem for me to 'call the shots'.
Also, I am noticing the sight picture is "shaking". I think it is mirage.
Hence, I am back to look for assistance in how I can estimate the wind more accurately.
Is there any book or website that has decent coverage on wind estimation and effect of mirage?
Thanks for helping a newbie on the longer range shooting.
S.

PS. I do have a wind gauge but it does help when trying to read the wind at 200 or 300 yd away.
 
Here is a bit from the Ultimate Sniper.

Mirage rises straight up-No wind
Mirage tips about 60*- 1-3MHP wind
Mirage tips about 45*- 4-7MPH wind
Mirage blows parallel- 8-12MPH wind

Hope this will help you.
 
Read all the books you can on the subject but nothing replaces trigger time. Shooting is only interesting when the wind is blowing. If it wasn't, everyone would be tied for first place.
Your scope might also be picking up the heat off the barrel which will cause a less than perfect sight picture.
 
Mirage can be useful in reading the wind as Scharfschütze has said, and it is particularly useful if the wind is bouncing back and forth or if it tends to fishtail. The subjects of wind and mirage is covered very well in the CD's available from Jim Ownes at JarHeadTop.com, which are aimed at helping the military high-power shooter.

The method I have been able to use successfully to adjust for wind by a simple formula that seems to work well enough for field shooting if not competitive shooting. Divide the range to the target by 100 and multiply that by the wind speed in MPH. Now divide that answer by a constant which is a diminishing value as range increases. Your best bet is to pull up an on line ballistics program and work out the constant for your particular bullet based on a 10 MPH cross wind, but you should find that it is close to 15 for ranges up to 500 yds, 14 at 600 yds, 13 at 700-900 yds, and 12 at 1000 yds, the answer being the number of minutes you need to adjust. If you have a pocket calculator with you its simpler to work than it sounds. An example might be if you were shooting at 300 yards in a 20 MPH wind . . .

3 X 20 = 60,
60/15 = 4 minutes

4 minutes would be the adjustment in a full value cross wind, if the wind was quartering, the correction would be half of that, or 2 minutes.

Some guys carry a small electronic wind meter, but these are pricy and provided you can determine the wind speed to within 5 MPH of true, your calculation will keep you on target. Wind is effected by the contours of the ground, by trees and vegetation, and wind is often different at different ranges, so while you might have a 5 MPH wind where you are the wind might be 12 MPH at your target. When dealing with this situation just remember that the close wind has more effect on your bullet than the far wind because of the amount of time the bullet is subjected to its effects.
 
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maynard said:
Read all the books you can on the subject but nothing replaces trigger time. Shooting is only interesting when the wind is blowing. If it wasn't, everyone would be tied for first place.
Your scope might also be picking up the heat off the barrel which will cause a less than perfect sight picture.
Click to expand...

Good point on the heat from the barrel. I will keep that in mind.
In the recent case, I was shooting in 1 C weather and it was the first 5 shots on the TRG so I do not think the barrel was that hot yet.
But I will keep an eye out when I shoot next time.
 
Scharfschütze said:
Here is a bit from the Ultimate Sniper.

Mirage rises straight up-No wind
Mirage tips about 60*- 1-3MHP wind
Mirage tips about 45*- 4-7MPH wind
Mirage blows parallel- 8-12MPH wind

Hope this will help you.
Click to expand...

One more question: how do you read the wind when it is more than 12 MPH at the target?
 
As has already been said,the effect the wind at the target has on bullet flight is minimal as the bullet is subjected to it for only a short time in its flight. Unless that wind (direction and strength) is prevalent at a greater portion of the flight path. If you are using a spotting scope you may want to have your spotter focused for an intermediate distance in the flight where you have determined the wind's effects will be the greatest and watch the mirage changes there. Try to focus on grass, proximate shrubbery or anything in the vicinity of where the wind is having the greatest effect.
 
Solar
You mention about reading up on wind and mirage in the thread title.
"The Rifle Shooter" & "High Power Rifle" by David Tubb are excellent.
Middleton Tompkins, who has been shooting high power for over 40 years,
is a multi-time winner at the Camp Perry high power matches and was the World FClass champion in 2005 and is considered to be one of the best wind shooters in the world also has a book. The title escapes me but I believe it
is still available and a look on the web would probably find it.
Don't get too caught up in the reading - there is nothing like 1st hand knowledge and experience.
Cheers
 
maynard said:
Read all the books you can on the subject but nothing replaces trigger time. Shooting is only interesting when the wind is blowing. If it wasn't, everyone would be tied for first place.
Your scope might also be picking up the heat off the barrel which will cause a less than perfect sight picture.
Click to expand...
Absolutely. That book I linked would be next to worthless without a ton of shooting. It's like a book on ###, it might give you the rough idea of what you're trying to accomplish, but it's not really the same :D
 
Any chance you can put up flags? or watch vegetation?

Judging high wind speeds is not easy but if you have objects to reference, you can learn with time.

The way I learn is to be able to spot every shot. I look at the conditions. Make an educated guess, hold off and fire. What happened? did I judge it right, too much, not enough?

Make notes of what happen and try again, repeat a few thousand times. Patterns will emerge and you will get better at 'guessing' where to hold.

It will get easier. Eventually, you will develop a feel for how much to lean into the wind by looking at your windage cues. It takes a lot of time.

But that is the real challenge in shooting accurately.

Jerry

PS 6mmBR.com has some great articles there on doping the winds.
 
Here are the targets that I shot today - all are 300 yards distance.
First group was supposed to be a 5 shots group using Hornady 168 gr A-Max 308 cal on a TRG-22. I have no idea what happen to Shot #5. So I decide to fire a 6th shot and it went to the same elevation as others. You can see the grouping info on the photo.
Hornady168A-Max6shots-300yd.jpg

I decided to try a 5 shots group with Hornady 168 gr BTHP 308 cal on the TRG. I think the shot landings are affected by the wind. You can read the shot sequence and the grouping from the photo.
Hornady168BTHP5shots-300yd-1.jpg

Question from a newbie: by doping the wind correctly, can I get a one hole group in 300 yards (i.e. all the shots touching each other)? Or, am I just asking for a pipe dream?
Right now, based on these targets, I am shooting sub MOA at 300 yards. Is there a way to get even better?
Any comment is appreciated as I am trying to get better.

S.
 
You need to stop taking the flyer out of the group when you measure it. They are all part of the group and help you determine your rifles potential with that load. By your numbered shots in photo #2 you can see where the 1st shot was fired then the wind picked up, for shot 2 & 3 the wind was slowing down, and for 4 & 5 was shot under a no wind condition. Not big deal thats what the knobs on the scope are for. If you can't read the wind before or during the increase in speed or let offs, aiming off won't do you much good.
To make a simple wind flag get some surveyors flagging tape (trail marking tape) cut a piece about 12" long and using an elastic band attach one end to an empty shell casing (9mm or .45 works great), stick a peice of wooden dowel into the ground and put the empty over it. You can move these quickly anywhere you want them so they are easy to see just before you squeeze the trigger.
 
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Solar, you will always be limited by the mechanical accuracy of your rifle.

If the rifle has the ability to shoot 1/4min or MOA, that is as good as you can drive it ON AVERAGE.

You may get the occasional group where the errors all fall into the same hole but that will not be the norm. Why most that compete or are interested in learning about the accuracy of their rifle, don't lean on one hero group but look at the average over many groups.

Sure, conditions matter and testing when air is calm will help you determine a baseline. Once you have a composite of what your rifle and you can do in ideal conditions, the goal is to be able to do this when then wind blows.

Otherwise, we would all compete with SKS's and get bug hole groups.

Jerry
 
maynard said:
To make a simple wind flag get some surveyors flagging tape (trail marking tape) cut a piece about 12" long and using an elastic band attach one end to an empty shell casing (9mm or .45 works great), stick a peice of wooden dowel into the ground and put the empty over it. You can move these quickly anywhere you want them so they are easy to see just before you squeeze the trigger.
Click to expand...

Great idea for the wind flag - thanks.
 
Thanks for all the comment and suggestion. I will do some reading and more practice.
Again thank you for sharing your knowledge with a newbie.
 
maynard said:
Read all the books you can on the subject but nothing replaces trigger time.
Click to expand...

I'd agree to a point, but I think even better than trigger time is spotting scope time with a good shooter. You get the shooter to fire a center hold and see where the bullet hits while watching the mirage. The more spotting you the netter you get at reading mirage. What sets a really good BPCR shooter from a decent one on a given day is the quality of their spotter. I know it's not entirely apples to apples (for the most part you don't have a scope on a BPCR) but time in the spotter's chair will give you a way better feel for subtle wind changes.
 
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