So let’s look at several methods of range estimation that can get us closer than just a wild guess.
•100 Yard unit-of-measure
•Appearance-of-objects
•Bracketing
•Halving method
•Range Card
•Laser Range Finder
•Combination Method
•Mil-Relation
100 Yard unit-of-measure
•Must visualize 100 yards on the ground
•Accurate to 500 yards
•Requires constant practice
Appearance-of-objects
•Determine range by the size and characteristics of an object
•Depends on visibility
•Requires constant practice
•200y--Clear in all detail, i.e. color of skin/hide/horns etc.
•300y--Clear body outline, face color good, remaining detail blurred.
•400y--Body outline clear, remaining detailed blurred.
•500y--Body tapers, head becomes indistinct.
•600y--Body now a wedge shape, no head apparent.
•700y--Solid wedge shape of outline of body
Bracketing
Used when the shooter assumes the target is no less than “X” meters away, but no more than “Y” meters away. Then the shooter uses the averages of the two distances as the estimated range.
Halving method
The hunter picks out a point half way to the target, estimates the range to that point and then doubles it. This works very well on the longer attempts. Many hunters have a fairly easy time estimating from 100 to 300 yards, but after that they struggle.
Range Card
A hunter can also use a range card to quickly determine ranges throughout a target area. Once a target is spotted the hunter determines where it is located on the range card. The range to target can then be approximated using pre-referenced target points.
The range card can be anything from a sketch to a digital photo of the hunting area with target reference point’s written on the picture/sketch. Snags, rock outcroppings, or any other terrain feature make great reference points. As a habit I make up a sketch of the ground I will be glassing as soon as I get set up and start ranging with my laser. That way if something happens and my laser won’t work I at least have some frame of reference to go off of and I am not out of business.
Laser Range Finder
•LRFs provide an extremely accurate and fast method of range estimating a target.
•Requires extra equipment (i.e., extra batteries, tripod, etc.)
•You must not rely on this only
Combination Method
Perfect conditions rarely exist in the field. One method of range estimation may not be enough. Terrain with a lot of dead space limits the accuracy of the 100-yard method.
Poor visibility limits the appearance of object method. But by combining 2 or more methods a hunter can arrive at a range estimation that is close to the actual range. Do not limit yourself!!
Mil/MOA-Relation
To begin to understand the use of a mil or moa reticle in estimating range we first need have an understanding of what each is.
MILS
A MIL or Mil-radian is an angular unit of measure. There are 6400 standardized (NATO) mils in a 360 degree circle. Since a MIL is an angular unit of measure it increases proportionately with distance.
Attachment 3803
NOTE: there is some confusion about” USMC” mils vs. standardized mils. The “USMC” mil is based on 6238 mils in circle Standardized is 6400. Both equal 3.6” @100 yards. Got it? Now forget about it.
MIL-RELATION FORMULA
Requires you to know the size of the target (in inches)
(in x .02778 x 1000) = Constant
or size in inches x 27.78 = constant
Divide constant by Number of mils read
Round answer to the nearest yard
SO:
Target size in inches X 27.78 = range to target in yards
Mil reading
If you insist on using meters:
Target size in inches X 25.4 = range to target in meters
Mil reading
Here is a tip I just learned while shooting with my new friend Darrell Holland a couple of weeks ago:
The above formula assumes that you’re measuring from the center of the stadia wire in the reticle to the center of another stadia wire. Very rarely can you use the center of the wire; you end up just “kissing” the edges of the target with the line. This throws off the Mil reading. He came up with a modified constant that allows for this. If you use the following formula when using the Mil-relation formula you will be more accurate.
Target size in inches X 29 = range to target in yards
Mil reading
Note the constant above. Don’t be a goof and do the entire math problem every time you punch in the numbers on your calculator. The constant is the constant because it’s constant you dig?
A 16” target X 29 will always be 464, a 36” target X 29 will always be 1044, so on and so on.
16” X 29 = 464 = 580 yards
.8 mils .8 mils
16” X 29 = 464 = 1325 yards
.35 mils .35mils
Same applies for using inches X 27.78 give them a try next time you’re shooting with your mil reticle and see how they work for you.
Attachment 3807
(the above are examples of “Hollands Advanced Reticle Technology” reticles in use)
MINUTES/MOA
A minute is also an angular unit of measure.In a circle there are 360 degrees. Each degree can be broken down further into minutes. There are 60 minutes in a degree. A minute of angle is 1/60th of a degree. An MOA equals a distance of 1.0472 inches at 100 yards and 2.9 centimeters at 100 meters. Since an MOA is an angular unit of measure it increases proportionately with distance.
Fractions are difficult to work with when making mental calculations, for this reason round down to 1 inch and up to 3 centimeters. In 1,000 meters this only causes a loss of ½ inch or 1.5 centimeter in accuracy.
Attachment 3806
To MOA a target:
Size of target in inches X 100 = range to target in yards
MOA reading in reticle
16” buck X 100 = 400 YARDS
4 MOA
16” buck X 100 = 914 YARDS
1.75 MOA
Attachment 3804
Some tips for accuracy:
•While using the mil/moa-relation formula, the key element is a steady position.
•Your position must be as steady as when you fire at a long-range target.
•If you are not steady, you cannot get an accurate mil/moa reading.
Some other things to consider with range estimation:•Your position must be as steady as when you fire at a long-range target.
•If you are not steady, you cannot get an accurate mil/moa reading.
Range can be determined by measuring or by estimating. Below are the three main factors that affect the appearance of objects when determining range by eye.
• Nature of the target
• Nature of the terrain
• Light Conditions
Nature of the target• Nature of the terrain
• Light Conditions
A target will appear closer if:
A target will appear more distant if:•The object has a regular outline
•An object contrasts with its background
•An object contrasts with its background
•The object has an irregular outline
•An object blends with its background
•The object is only partially exposed
Nature of the terrain•An object blends with its background
•The object is only partially exposed
A target will appear closer:
A target will appear farther:•When observing over smooth terrain
•When observing across a depression, when most of which is hidden from view
•When looking uphill
•When looking down a straight, open road, or along railroad tracks
•When observing across a depression, when most of which is hidden from view
•When looking uphill
•When looking down a straight, open road, or along railroad tracks
•If the observer’s eye follows the contours of the terrain
•When observing across a depression, all of which is visible
•When field of vision is narrowly confined
Light conditions •When observing across a depression, all of which is visible
•When field of vision is narrowly confined
The target will appear closer:
A target will appear farther:•When a target can be clearly seen
•When a target is viewed in full sunlight
•When the sun is behind the viewer
•When a target is viewed in full sunlight
•When the sun is behind the viewer
•If the observer’s eye follows the contours of the terrain
•When observing across a depression, all of which is visible
•When field of vision is narrowly confined
A hunter’s ability to range is as critical as his or her ability to shoot accurately. While a laser range finder will always be more accurate than estimation by eye or using MIL/MOA relation, having more tools in your tool box may be the difference between a hunt being successful or going home empty handed. Don’t let your hunt of a lifetime end in failure because your laser let you down. •When observing across a depression, all of which is visible
•When field of vision is narrowly confined
So using your new found skill scroll down and figure out how far away the buck is:
Attachment 3805
Answer: TO DANG CLOSE TO WORRY ABOUT IT SHOOT HIM!!!!!
A note from Nate: a big thanks to Darrell Holland of Holland Gunsmiths for sharing the diagrams for the article and giving me permission to share his mil relation technique. This article was partially created from a power point presentation that my section put together for a marksmanship course in Japan in 2007. It is dedicated to my former soldiers of 2-162 INF sniper section, currently in Iraq for their second tour and on their way home shortly.
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