A Short Course On Reading the Wind
Let me begin by saying that I shoot at the expert level in highpower rifle
competitions. There are people who shoot at the master level and, if you
know one, you should talk to him when you are ready to shoot at that level.
However, expert level shooting is all that is required for combat sniping. I
will define expert wind reading as the ability, under favorable conditions, to
estimate the wind speed in 2½ mph increments. Sharpshooter wind reading
would be in 5 mph increments. At 300 yards, the range your rifle is zeroed
for and that you will be practicing at, a sharpshooter adjusts his windage in
whole MOA increments and an expert adjusts his in half MOA increments.
By "favorable conditions" I mean one of two things:
(A) There is smoke or
dust nearby, allowing you to measure the wind by how fast it is drifting, or
(B) It is a hot day and there is an object with a well defined horizontal edge
near the target on which you can see the mirage. "Mirage" refers to the heat
waves which rise off of hot objects. It is easier to observe in a 50x spotting
scope than in a 10x rifle scope, but it is still visible. You can see it with
your naked eye if you look across the hood of your car on a hot day. In still
conditions, heat waves appear as wavy vertical lines. Five mph winds bend
them over at about a 30º angle while ten mph winds bend them over at about
a 60º angle. Fifteen mph winds bend them over flat so it is no longer feasible
to measure the wind speed this way. If you look at a horizontal edge,
like a rooftop, the heat waves seem to be running along it.
If there is a large parallel component to the wind (it is blowing mostly towards
or away from you), then the angle of the mirage still measures the
perpendicular component of the wind, but the parallel component will make
the heat waves wiggle. This is called a "boiling" mirage and is a difficult
shot because a wind's direction shifts more often than it's magnitude shifts,
causing the perpendicular component to vary more rapidly than if the wind
were mostly perpendicular, and those changes are hard to see because of the
wiggle. In cases like this it is not possible to dial your windage up and down
fast enough to keep up with the variations in the wind, so you should set
your scope for the least wind that you are seeing and then fire the next time
the wind dies down.
Condition (A) is easy to obtain at any public range because there are always
lots of people blasting away at fifty and hundred yard targets. Condition (B)
is easy to obtain at rifle matches because you can look at the target boards.
In combat, condition (A) is obtained in bombed out cities while condition
(B) is obtained in still intact cities. You must practice with both.
Unfavorable conditions are when neither (A) or (B) are obtained, in which
case you have to resort to looking at the greenery. Roughly, when grass
sways and leaves flutter, there is a five mph wind. When tree branches
sway, there is a ten mph wind. When small trees sway, there is a fifteen mph
wind. What is most unfavorable about this technique is that the swaying of
tree branches tells you nothing about the direction of the wind. For that you
need another technique, the best one being to throw some grass up in the air.
If 0º is perpendicular to your shot and 90º. is in line with the target (it
doesn't matter if it is towards you or away from you), then assign full value
to any wind from 0º to 45º. Assign half value to any wind between 45º and
75º. Ignore winds between 75º and 90º (note 1)
The best thing about favorable conditions is that, when looking at dust or
heat waves through your scope, you are only seeing the perpendicular component
of their movement. Thus, you do not need to know what direction
the wind is blowing because you are measuring the only part of the wind
(the perpendicular part) that matters to you. The easiest way to identify beginners
at a rifle match is that they are always licking their fingers and holding
them up to determine the direction of the wind. That is because they are
thinking of unfavorable conditions where the wind speed is determined with
one technique while wind direction is determined with another.
The wind near you is more important than the wind near the target. That is
because, if the wind near you blows your bullet off course, it will continue in
that direction. If the wind near the target blows your bullet off course, it will
strike the target before it has gone far away. When looking at dust, you
should judge how much importance to give it based on its distance from you.
Also, the wind you feel on your face is the most important, so heed it. Heat
waves are transparent, however, so it is not clear how far away the mirage is
that you are seeing through your scope.
Rifle competitors will focus their spotting scope at three hundred yards so,
when they move back to the six hundred yard line, they will be seeing the
near mirage. This only works with powerful spotting scopes, not with 10x
rifle scopes. To see why, recall that, when taking someone's photo outdoors,
photographers are advised to stand back and zoom in on her. This is
because, the higher the magnification used, the shorter the focal range. If
you zoom in on her, the girl will be in sharp focus while the bushes behind
her will be a green blur. At low magnification, both the girl and the bushes
will be in good, but not sharp, focus and the picture will appear cluttered because
you can see every leaf in the bushes. Similarly, 50x Kowa spotting
scopes can focus on just the 300 yard mirage while 10x rifle scopes show
everything from 100 yards out to infinity in equal, if not great, clarity. Focus
your scope on a clear day and then don't monkey with it in the field.
Reading the wind is not your highest priority in combat. Finding the enemy
sniper and getting to the trigger first is more important, and for that you need
a scope of no more than about 12x;. The high magnification scopes that
seem to be all the rage nowadays have far too small a field of view for combat
use. Also, they require readjusting the focus depending on how far away
the target is. So, forego some wind reading ability and buy a 10x scope.
Also, when buying your scope, remember that your objective is mediumrange
sniping, which means from about 200 to 500 yards with occasional
600 yard shots. If you look at a Leupold adjustable objective, you can see
that only an eighth inch separates the 200 and 400 yard marks, but 1½" separate
the 25 and 100 yard marks, so this adjustment is really for .22 RF rifles.
Non-adjustable scopes can be set to be parallax free at any range you chose;
ask for 300 yards. 30mm tubes have a large range of adjustment, but Aguilar
System shooters are holding over on the mil-dots, so a 1" tube is sufficient.
50mm objectives sit too high on the rifle, so get a 40 mm lens.
Practicing with a rifle is pointless unless you are getting immediate feedback
after each shot. If you fire a box of ammunition and then, when the rangemaster
calls for a cease fire, you walk down range and discover a long horizontal
string of bullet holes, all you have really learned is that you are a
lousy shot. You have not learned how to become a better one. In the past,
getting feedback on your wind reading could only be accomplished at rifle
matches when you had someone pulling the target for you. However, now
we have Shoot N-C targets, so you can do this alone at a public range.
You are going to be estimating the wind speed in either 5 or 2½ mph increments
and it is important to be systematic about adjusting your windage dial
in only those increments. Just because your scope has quarter MOA clicks
does not mean you are going to be using them all. At 300 yards a 10 mph
wind requires 2 MOA windage, so a 5 mph wind requires 1 MOA and a fifteen
mph wind requires 3 MOA. So, for sharpshooter level wind reading,
you will be adjusting your windage dial only in whole MOA increments. Do
not make any finer adjustments until you are confident that you know the
difference between a zero, five, ten or fifteen mph wind.
While Shoot N-C targets are a fine thing, the problem with practicing alone
at a public range is that it is boring and not very goal oriented. If your only
goal is to shoot a tight group so you can take the target home and show it off
to your friends, this is more easily accomplished, not by learning to read the
wind, but simply by trying to show up at the range on a day when there isn't
any wind. However, if you make an occasion out of promoting yourself
from sharpshooter to expert, and always behave as one or the other by estimating
the wind in either 5 or 2½ mph increments, you will have a goal. But
don't be too anxious: Sharpshooter is sufficient for shooting fat people.
But what if you do not have access to a 300 yard rifle range? Should you
practice at 100 yards? No. That is really a waste of ammunition. You will
need to drive to a 300 yard rifle range at least once to zero your rifle. However,
to learn to read the wind, you should buy a .22 RF target rifle and a
case of subsonic match grade ammunition for it. I use Federal Gold Medal
UMB1 but, as long as you are using ammunition that is less than or close to
the speed of sound (1125 fps), the windage needed at 50 yards is the same as
the windage used on your highpower rifle at 300 yards. Practicing at 100
yards with a .22 is equivalent to practicing at 500 yards with a highpower
rifle. Even if you have access to a 300 yard range, buying a .22 target rifle is
not a bad idea. It costs a dollar every time you fire your highpower rifle, but
even the most expensive .22 ammunition is a tenth that much.
If you have read this far and are confused, let me conclude with a rule of
thumb that is better than no wind reading at all but will avoid any really
gross windage corrections: At any range out to 400 yards, think "light "
"medium" or "heavy" and give them one, two or three MOA windage. If
you don't have finger adjustable dials, "heavy" is one mil hold into.
A 300 yard rosette of the type popularized by James Owens, but with MOA adjustments
consistant with the Aguilar System for Medium-Range Sniping. Double all the MOA
adjustments for 500 yards. I do not really recommend the use of rosettes, but I have included
one for the benefit of Owens’ former students.
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