Just another way of explaining the wind effect on the bullet is, think of it like MOA, a small movement at the rifle has a larger difference down range. If that push is caused closer to the target the less the change will be.I know there is lots more variables but this is how I was explained when I started shooting F Class 5 years ago. I hope it makes a little clearer for some people
E.g. shooting 1000 yards,if the bullet gets pushed an inch at 900 yards it will move effectively 9 inches on the target, similar to mid range wind if the bullet was pushed an inch at the 400 yard mark it would only be moved a 4 inches on the target.

Hope it makes sense, pretty simple I think anyway

RUNAS

quote:

if the bullet gets pushed an inch at 900 yards it will move effectively 9 inches on the target

Sorry, I don't understand this! Do you mean pushed an inch at 100 yards?
peter.

I think if you substitute MOA vs Inch it would be clearer?? 1moa @ 400=4" and 1moa @ 900=9", but not sure of the point being made here??

This general concept/system is very interesting, but, IMO, has little application to hunters. Obviously it has military use but I think it is waaay beyond what I would call an ethical hunting tool, even assuming it does all it is claimed to do.

Ok I will try to make it clearer without wearing my fingers to the bone typing.

Instructor Im trying to get the guys who do not agree or understand the theory of wind has a greater effect on the bullet further away from the target than closer, regardless of FPS of bullet in flight.

This is simulated in PERFECT conditions,there is no other conditions apart from wind in the specifc parts, so after that assume there is no other wind drift
Your at the 1000 yrd mound with ZERO wind wound on your scope, 100 yards away is enough wind to move the bullet in flight 1 MOA off course, as the bullet travels down range that bullet remains on the same path for the next 900 yards 1 MOA off course which will relate to 9 MOA or 9"(more or less) from centre when bullet reaches the target.
Same senario but the wind has NO effect the Bullet until the LAST 200 yrds, once again there is enough wind to push bullet 1 MOA off course which on the target only equates to 2 MOA or 2" (more or less).

I hope that clarifys it a little more, I was using my cell last night to send reply so I tried to keep it to a minimum.

RUNAS

Runas,
I understand about the matter of bullet being pushed 1"/1moa to either right or left some 100yds from the muzzle and yes, at 1000yds it would actually be some 10"(minute of angle at 1000yds, 10times from 100yds.)
However, I believe you will find that most operate under the assumption and in fact, reality, that the wind has the most impact on the bullets flight closer to the muzzle, not further down range.
That is not to say that downrange wind/gusts, etc. will not have influence on the drift of the bullet, but for shooting purposes and trying to "dope" the wind it is a general practice to estimate wind speed/direction some distance near half way of the flight. It is a common to use your spotting scope and focus it some distance back from the target itself to determine any mirage/wind conditions that may exist and adj. sight accordingly. Nothing wrong with setting focus at the target face to see if there is anything going on out there as well, but the instant the bullet is exposed to whatever wind is taking place, it's course is pretty well set and to not adjust for that would result in not desired shot placement. Some don't adhere to this practice and some do. If you can make good wind calls by attempting to read the wind near or at the target, good for you, whatever works is the name of the game. Excellent booklet published by Mr.Jim Owens titled "Reading the Wind." Does it have all the answers, no, but very good instructions and assitance found there.
Firing solution question:
Range of shot, 1000yds. Wind speed determined to be @ 9mph. Wind direction from right to left, 2 o'clock to 8 o'clock. Cartridge is 308/30-06 class. How much windage would you apply under these conditions? Would you leave elevation adjustments as previous shots? Just a sample of typical problems dealt with and former shooting group used to sit around at the range and do estimates and had to call the shots to verify. Some were quite good shots and would call X rings be it 12 o'clock, 3 o'clock, etc. etc. but this took place at the 600yd range, not 1000yds. Very few can call clock placement in the X ring at 1000yds.

Yes Instructor I agree with you, the range I shoot on here in NZ has some of the trickest wind to read in the country, I personally do use my scope to try and pick up mid range wind via mirage, as you have said,I was only trying to illustrate extremes for folks so they can perhaps get a better idea of wind effects.

Ive had people ask me how to read wind, mirage etc, I only tell them the theory, rest is up to them with quality range time,sorry there is no quick answer.

However I still find the toughest calls to make are elevation shots because of wind.

RUNAS

Normally a tail wind or head wind is of little concern elevation wise, but it can have some impact. At Oak Ridge, TN range, one of the nicest ones around, and at the 1000yd line there is a drop off of quite a few feet something like 50-60' in front of you and some small grass/weeds along the edge. Learned the hard way if you do not observe the wind blowing toward you and those weeds/grass moving a bit, it will squirt your bullet out of the 10 ring.
You either wait for no visible wind or adjust accordingly. Have always been told that if you view a boiling mirage "out there" do not shoot for it will possibly raise the flight of the bullet. Again, wait or adjust. Unless I am having a real bad day and running out of time, I always wait till conditions are in my favor.
I had mentioned earlier that I adjust elevation along with windage at 600-1000yds, but don't really have any exact method for doing that other feedback of spotter on target face. Your point about no quick answers is very true, no substitute for time behind the gun. You mentioned F class and have yet to do that but shoot prone/sling/mat/ironsights and been doing so for nearly 60 years now and eyes not as sharp as once, but seems like each match, regulation or practice, learn something new. DOPE, data of previous experience, keeps increasing.

quote:

Originally posted by Instructor:
Normally a tail wind or head wind is of little concern elevation wise, but it can have some impact. At Oak Ridge, TN range, one of the nicest ones around, and at the 1000yd line there is a drop off of quite a few feet something like 50-60' in front of you and some small grass/weeds along the edge. Learned the hard way if you do not observe the wind blowing toward you and those weeds/grass moving a bit, it will squirt your bullet out of the 10 ring.
You either wait for no visible wind or adjust accordingly. Have always been told that if you view a boiling mirage "out there" do not shoot for it will possibly raise the flight of the bullet. Again, wait or adjust. Unless I am having a real bad day and running out of time, I always wait till conditions are in my favor.
I had mentioned earlier that I adjust elevation along with windage at 600-1000yds, but don't really have any exact method for doing that other feedback of spotter on target face. Your point about no quick answers is very true, no substitute for time behind the gun. You mentioned F class and have yet to do that but shoot prone/sling/mat/ironsights and been doing so for nearly 60 years now and eyes not as sharp as once, but seems like each match, regulation or practice, learn something new. DOPE, data of previous experience, keeps increasing.

Instructor:

I notice the same thing when shooting at one of my AZ locations: when the wind blows from behind, it actually creates an updraft because my target is on a hill quite a ways up. If you think about it, wind that hits a hill has to go somewhere, and the only somewhere is up.

I went out shooting yesterday afternoon; shot once at 820, 650, 500, and 400. Called the wind as 1.1 mils at 820, hit about 3 inches right of point of aim and four inches low. At 650 I called .7 mils and hit left 4 inches and 2 inches high. At 500 I called 1/2 mil and obliterated the 3 inch aiming cirlce (painted on a rock). At 400 I hit the 3 inch circle at the top; held .3 mils. All were done using my bipod sit with shooting sling position. I don't post pics but if someone wants to I can send them. I got a cool pic of a big tarantula as well.

I was pretty happy with those results, but I can't say it means I should shoot game at 800 yards.

There is another vertical component of wind drift. If a bullet is blowen to the right, with a right hand twist barrel, it will also go lower on the target. A variable cross wind does not produce a horizontal group at 1000 yds, but rather a diagional group, with the rounds that have been blowen further being lower. I do not know if this has to do with the action of the bullet spin against the wind or disruption of gyroscopic effect.

Yes the rule of thumb is with a right hand twist barrel, left/ high.....right/low for me thats about where it ends! How high or how low is the million dollar answer
Its probably why I keep going back
Highjacking this thread something cruel too! Soory.

Bubba - is that you?

quote:

Originally posted by Vince Hazen:
Bubba - is that you?

Might be. Hows it going. Great shooting with you the other day

quote:

Originally posted by 338zmag:

quote:

Originally posted by Instructor:
Not seeing any obvious wind issues at the extended range best practice I have found is adjust for whatever wind for the first 1/3 or 1/2 of the distance at hand. Have always been told that the impact of the wind on the flight of the bullet is most felt/greatest the first portion of the flight not the final portion.

If I am understanding your statement correctly, I would disagree. The bullet is going faster in the first part of the flight. Therefore the wind has less time to impact it, as opposed to the latter half when the bullet is slowing. A slower bullet has more time to be impacted by the wind, since it spends more time in the second half of the flight than the first half.

This guy explains it in this video.
http://www.youtube.com/watch?v...WUy6Q&feature=relmfu

You have it backwards...

My God this is Long Range Shooting 101 here... Going to have to get my wind stuff out and post it again...