Battlesights
In the section on accessories,
I referred to target acquisition devices (I.E. sights, and scopes). I did
not go into a great deal of detail about them because the subject is expansive,
and I could very likely dedicate an entire site to this one area. This
section will concern itself with rifle sights, since only a fool would
choose a pistol as a primary battle weapon. Actually, the term battlesight
can have two meanings. A battlesight is a sight setting utilizing what
hunters call a point blank range. This is an imprecise, but versatile method
of sighting in iron sights, which allows a shooter to quickly engage a
target at a variety of ranges. A battlesight can also refer to a piece
of sighting equipment particularly well suited for combat.
Point blank, and the Battlesight
The traditional battlesight in most branches of the
military is a setting of two to three hundred yards, though this can vary
from caliber to caliber. The idea behind the battlesight is that there
is a lethal area about the middle of the human body which is approximately
six to nine inches in diameter. In theory, a hit anywhere in this circle
will be disabling. So rather than having to estimate range, and calculate
drop to the target, once point blank range is set, the shooter need only
aim for the middle of the torso and fire. The bullet should impact within
the lethal area at all ranges from the muzzle, out to several hundred yards.
Precision shooters look with disdain upon this method, as it flies in the
face of all the skills they have so painstakingly acquired, but within
it's limitations this can be a very effective means of placing one's fire
as quickly as possible where it will do the most good. A chart of the point
blank range settings, and effective distances for various cartridges is
shown below.
Caliber |
Point Blank Setting |
Mid Range |
Far range |
.223 (55gr) |
300yds (50yds) |
+5.4"@150yds |
-5.9"@350yds |
.223 (M-193 68gr) |
300yds |
+5.7"@150yds |
-5.9"@350yds |
.308 (Military ball) |
300yds |
+5.4"@150yds |
-5.1"@350yds |
.308 (168gr sniper) |
300yds |
+5.2"@150yds |
-5.1"@350yds |
30-06 |
350yds |
+7.3"@200yds |
-5.7"@400yds |
.300 Win Mag |
350yds |
+5.9"@200yds |
-4.7"@400yds |
44Magnum pistol |
125yds |
+5.5"@75yds |
+6.1"@150yds |
As can be seen from the chart, this is anything but
a precision method of shooting. At the near and far extremes of the
effective ranges, the shots will tend to be gutshots, or groin shots. Towards
the middle they will hit high, up around the collar or even the neck. This
method depends upon the fact that a rifle cartridge is very much more lethal
than a pistol round. Hits which would be ineffective with a pistol can
be devastating when made with a rifle. Unfortunately, dependence upon this
method will develop poor shooting habits, and may not be effective against
smaller, or partially shielded targets where the size of the effective
area has been reduced. As an illustration of the effectiveness of Rifles
over pistols, I have included the .44 Magnum for comparison.
Iron Sights
The most popular standard military sight is the
aperture or peep sight. This uses a standard post for the front sight,
and a small hole as the rear sight. The main advantage of this sight is
it's quickness. Target acquisition is very fast, though accuracy may suffer
a bit. This sight takes advantage of the fact that for most people, centering
an object within a circle is a very fast and natural visual instinct. Some
people do this better than others, and some people do not do this well
at all, but for most of us this is a fairly fast and easy to use sighting
system. This is not the best choice for very accurate shooting, as even
the best shots are only "eyeballing" the sight picture. This particular
system has been used on every American rifle since W.W.II, and is on the
current version of the M-16. This major criticisms of this sight have to
do with it's lack of precision, and poor low light performance, though
no iron sight performs particularly well in low light.
There is a variation of the peep sight, used by
H&K, which I consider to be the best battle sight available. The H&K
sight uses a rotating drum with a series of holes calibrated for different
ranges as the rear sight. The front sight is a post with a ring set around
it. The tip of the front post sits in the center of the ring, and when
the shooter sights through the rear aperture, the front ring appears to
be the same size as the rear aperture, with the point of impact along the
top of the front post. This is a wonderfully quick, and also very precise
aiming system, and I can think of no way to improve upon it without going
to an optical sight.
Optical Sights
Optical sights are getting to be standard equipment
on hunting rifles and are becoming more common on military rifles as well.
Until recently, the military was wary of using optical sights on it's rifles
except for special purpose units like those using snipers. The objections
were primarily focused (so to speak) on the fragility of the scopes themselves.
There was also the matter of slow target acquisition (I.E. a scope is much
more deliberate and slow to use than iron sights), and the limited field
of view offered by most scopes. In the minds of many of the military brass,
a scope was just one more thing for a soldier to lose, break, and have
to learn. Many of these problems (field of view, fragility) have been greatly
reduced in the last several decades. Scopes are becoming smaller, lighter,
sturdier, and easier to set up and use. Most modern scopes have, at least,
an incidental way to calculate range and drop, and special low power, wide
field of view scopes, along with zoom scopes, have made the scoped rifle
almost as quick as it's iron sighted counterpart. British soldiers are
now issued a rifle equipped with a 4X optical sight; predictably, this
rifle also has a set of iron sights. This four power scope is at the high
end of magnification used in non-sniper battlesights. Most assault rifles
with integral scopes tend to have a magnification of around 1.5X. Scopes
of this power give little, if any, increase of effective range, but do
improve speed, and considerably improve accuracy. The low power permits
a wide field of view and a good range of eye relief, which enhance speed
and battlefield awareness.
Range Estimating Scopes
Most scopes have some means of calculating range, whether
designed into them as a ranging device, or simply as a sighting aid. Before
any pretense can be made about being able to range optically, the shooter
must be familiar with what an angular measure is, and in particular what
a minute of arc is. A circle is divided into 360 degrees, and each degree
is divided into sixty minutes of arc (you have already guessed that each
minute of arc is divided into sixty seconds of arc, but this level of precision
is not addressed by shooters). For the mathematically minded, 21600 minutes
of arc are in a full circle, so as you can see, this is would seem to be
a pretty small measurement. A fortunate coincidence makes 1 moa equal to
1" at 100 yards, or at any rate they are close enough so that the difference
is negligible (1.047" to be exact). Because the moa is an angular measure,
it changes in a completely predictable and linear way over distance. At
200 yards, 1 moa equals 2"; at 300 yards it is 3", and so on. This makes
it possible to calculate the angular size of any element or aiming aid
within a scope, and knowing this makes it possible to use virtually any
scope as a ranging device. The other major angular measurement is the mil,
which is used in a special scope called a mil-dot scope. One mil is equal
to 1/6400th of a circle, or 3.438 moa. This would seem to be a pretty odd
number to pick, but there is a reason it was chosen. At any distance, a
mil has an angular measurement of 1 to 1000, which is to say, at 1000 feet
1 mil is equal to 1 foot, at 1000 yards 1 mil is equal to one yard. The
virtues of the mil will be referred to in a latter section.
The Duplex Reticle
Though not initially designed as a ranging scope, there is some ranging
potential in this, the most popular of all Reticle designs, though taking
advantage of this requires the shooter to learn his scope, and his loads.
The crosshairs on a duplex reticle will be thick at the edges, with a thinner
set of hairs at the center. The angular measure of these hairs varies from
scope to scope, and must be determined by noting the subtention (the amount
of area covered) of the hairs on objects of known size at known distances.
The angular measure in minutes of arc, or mils may then be determined mathematically.
This would seem to be easy enough, but there is a complication. Most of
today's scopes are zooms, and most have the hairs set in the focus plane
of the ocular. What this means is that the hairs will stay the same apparent
size as the scope is zoomed, changing their angular size. The shooter must
either always range with the scope at the same power, or he must calculate,
and learn to use a number of different angular measurements at differing
powers. It is generally best to range at the highest power, rather than
commit one's self to the impossible task of learning an infinite number
of sizes, measures, and ranges. There are two clear constant angular measures
in a duplex scope. The first is the width of the thicker, outside part
of the hairs; the second is the space between the edges of the thicker
portions. Generally, there are between 8 and 30 moa in this open area where
the hairs thin. In order for the range information to be of any value,
the shooter must be familiar with the amount of drop a given load has at
a given distance, and must be familiar with the vertical adjustment of
his scope. The old military shooters used to call these adjustments "come
ups".
The use of come ups is very simple, and is
a matter of knowing the range of the target, the drop of the round being
fired, and the vertical adjustments of the scope. As an example, you have
a target at 300 yards, and your scope is sighted in at 100 yards. if you
fire dead on, you know that your shot will be low. You also know that each
click of vertical adjustment on your scope raises the hairs 1/4 of a moa
(minute of arc). Being a dedicated sport shooter, you also know that between
100 and 300 yards, your favorite load drops 16" (or if you don't know,
you have a little "come up card" taped to your rifle stock, or slid up
your sleeve). Since you know that 1 moa equals 1" at 100 yards, you know
that 1 moa also equals 3" at three hundred yards. Knowing this, you can
calculate that at 300 yards you would have to raise your point of aim by
5 1/5 moa (we will settle for 5 1/4 moa, since the adjustments on the scope
are in increments of 1/4 moa). It will take 21 clicks of vertical adjustment
to properly set the hairs for the shot.
Stadia Ranging Scopes
Most scope manufacturers offer
at least one model of ranging scope for the hunter and sportsman. These
tend to use the stadia method by which a target of known size is bracketed
between a pair of lines (appropriately called stadia lines). Without exception
these are zoom scopes. This is a somewhat more precise method than the
use of a duplex reticle, but still leaves much to be desired. The main
drawback of this method is it's slowness. The shooter zooms the scope in
and out until the appropriate area is bracketed by the stationary stadia
lines, after which the range is read off of a calibrated circle set around
the zoom ring. After determining the range, the shooter must then click
the range adjustment dial to the appropriate setting to bring the crosshairs
to the proper point of aim. He may now bring his rifle to bear on the target
and fire, provided the target hasn't found something better to do then
stand there waiting to be shot.
This is somewhat better than the use of the duplex
reticle because the stadia lines are close enough together that smaller
targets, and longer ranges may be calculated more exactly. The come ups
are replaced by a calibrated dial, set over the vertical adjustment on
the scope, increasing speed a bit, but also losing some of the precision
gained by the better ranging ability of the stadia lines over that of the
duplex.
One problem with the stadia scope is that it is
not the most precise tool in the world. Certainly all optical ranging methods
make use of a certain amount of estimation, but the stadia scope has three
distinct fields of estimate, each of which adds it's own margin of error.
The first concerns the well known fact that the sizes of natural objects
vary. All deer do not have 18" briskets, nor are all men 5'9" tall; this
introduces the first variable. Second, the ranging ring, and the zoom optics
of the scope are not perfect, and even if they were, there is no precise
marking of range to go by; another variable. Third, The range settings
for the cross hairs are not absolutely accurate, and even if they were
there is some mechanical imprecision in the mechanism itself, introducing
yet another element of error. The Stadia method is marginally accurate,
but very slow, making it an acceptable, but not ideal system.
The Art Scope
This was THE ranging and sniping scope during
the Viet Nam War, and is still a well regarded design, though it does have
it's drawbacks. The leatherwood company which first designed and built
these scopes is still in business, and still produces an updated version
of this well regarded scope. The range is determined in a fashion similar
to that of the stadia scope. The attraction of this scope is that it determines
the range, and sets the bullet drop compensation in one step. This is done
through a clever set of cams in the base of the scope which raises or lowers
the rear of the scope as it is zoomed. Once your target is properly bracketed,
by zooming the scope, you need only aim dead on, and fire. The older version
of the scope used a pair of stadia lines set in the vertical hair; the
newer style has a set of horizontal hairs which subtend 18" in the civilian
model, or 1 meter in the military design. the company may be found at http://www.leatherwoodsporter.com/
There are a couple of problems, or at any rate irritations,
with this scope. The first is that the scope is useless without it's special,
and rather delicately calibrated, base. Both scope and base must be handled
rather carefully, and kept in adjustment. The second is that the shooter
is locked into using a specific magnification at a given range. The scope
is configured to range at 300 yards while at 3x, 400 yards at 4x, etc.
As was mentioned, this is more of an irritation than a problem Since this
is a 3-9 power scope, it can be inferred that it will range accurately
from 300 to 900 yards.
Another scope which ranges and compensates in one
step is the Shepherd scope http://www.shepherdscopes.com/
This scope does internally, what the ART scope does with external cams,
and the whole idea of the scope fascinates me. Both sites are worth a visit
for those interested in seeing just how sophisticated a sniper scope can
get.
The Mil-Dot Scope
At first
glance, this would seem to be a duplex scope, but upon closer examination,
a row of dots may be
seen running across the thinner part of the hairs. This is my personal
favorite for versatility, and is the only design available for some calibers
and applications. The mil system was initially used by artillerymen, and
made corrections by forward observers much easier, and more accurate to
implement. As was mentioned above, a mil is 1/6400 of a circle, giving
it a distance to area ratio of 1000. This was very handy for adjusting
fire. The artillerymen would know their range by the elevations set on
their guns. The forward observer would give corrections in yards which
could easily be converted to mil measurements and adjusted on the guns.
Though a mil is a much larger measurement than a moa, and the artillerymen
generally fire at targets much farther away than anything a rifleman usually
takes aim at, this is plenty precise enough for 4" to 8" shells full of
high explosive. Though designed for compensation and adjustment of fire,
the mil system may be used to range as well as compensate. It also has
the advantage of not being tied to any particular caliber as the proprietary
reticles listed below are, while being almost as fast. The cross hairs
are adorned with precisely spaced and sized dots measuring exactly 1 mil
from center to center. The thin part of the cross hairs is ten mils high
by ten mils wide.
I have included a small range card which should
give some idea of how the mil dot system is used to range, and should also
give an indication of the power, and versatility of the system. A skilled
shooter, with
or without range cards, equipped with a mil dot sight should be able to
range, calculate drop, and fire, all without ever having to take his finger
off of the trigger, or take his eye from the scope. With the range card,
I have included a diagram of what a mil dot is, and the various measurements
of the components of the mil dot system. As can be seen, measurements down
to 1/4 of a mil may be quickly and accurately made. As a mil is defined
here as 3.438 moa, it may be further seen that measure of less that 1 moa
can be determined. This is a considerable amount of precision for a system
of such speed, and simplicity. The lack of delicate parts which may be
damaged, or of moving parts which may be misaligned, adds to the robustness
of the design.
Proprietary Reticles
The quickest and most accurate method, though sharply
limited to certain calibers, and in some cases certain loads. These scopes
tend to be made specifically for military applications, and are therefore
commonly available for military calibers. This is the best choice for a
long range scope, provided a model is made for the particular caliber and
load you fire. These have etched glass reticles rather than drawn hairs,
and are generally quite expensive. As much as I sing the praises of the
mil dot system, and recommend it without reserve, I do favor the dedicated,
proprietary reticle, and recommend it if one maybe found for the particular
caliber and load being used. The best source for proprietary reticles is
probably Springfield Armory, which offers a number of different models
designed for a range of military calibers.
In this particular scope, the zero is set at 200yds.
As may be seen, there are a series of calibrated shapes set in the field
of the scope. These shapes are used to estimate range, by referencing the
size of the target. Upon determining range, the appropriate crosshair is
used. This scope is right on the money, with the proper load, out to 1000yards.