ASK THE EXPERTS:
What is a MILDOT SCOPE?
The best way to answer is in the Total Participant Involvement (HANDS ON) fashion of HGR Firearms. To Understand a MILDOT concept, we have to get technical with the basics of navigation, geometry, and some science involving wind drift and gravity.
The MILDOT reticle doesn’t refer to military, but Mildot Scopes are used by military, law enforcement, and some hunters. The basic Mildot reticle looks like this:
From the center you have marks that can be used to measure distance and size of the target. It can “lead” a moving target as well. Here’s the technical information to help understand.
MILLIRADIAN: The term “Mil Dot” is an abbreviation for the term “Milliradian”. You probably know that a complete circle is comprised of “degrees of angle”, 360 degrees in a full circle. Think of a compose face or dial, each angle or degree is measured to allow you to walk from point A to point B and stay on a straight course. That straight line is “a single degree” or 1/360 of a circle. As the circle becomes larger, the length of the Degree also gets longer, and so does the distance between the degrees of angle. The distance between the degrees of angle is further divided into “minutes of angle” and there are 60 “minutes” between each individual degree. This is further divided into “Seconds” on the same ratio, but we don’t deal with that with shooting, but for navigation or calling in an AIR STRIKE it may be necessary.
Distance: At 100 yards the distance or angle between “one minute” is 1 inch. So if the center of two 100 yard bullets holes are one inch apart, we call that “ a minute of angle” or “minute of angle group”. The ratio stays the same even if that group was at 400 yards (4 inch group at 400 = 1 minute of angle at 100 yds).
The MILLIRADIAN, or one mil of angle, is about 3.6 inches in diameter at 100 yards distance. For fast calculations it’s close to 3.5 inches and that’s the standard reference. This holds true for fixed power scopes, but for variable power it is only true at the highest power zoom setting (3x9 power would be 3.5 inches at 100 yards on “9x”). So if you’re looking through the scope at the paper hits, and the centers of the 2 bullets touch the Bullseye (3.5 inches in diameter), then you are at 100 yards distance. If it appears that the 2 bullet centers are about half the Bullseye apart, then you are about 200 yards away. If the bullet centers appear to span across 3 dots (1 between the holes) then you are 50 yards away.
Tactical and some hunting scopes also have vertical “hack marks” which can be used to measure height of an object or target. For instance, you’re hunting a bear, and you see him stand up on his hind legs, and the Mildots are 2 mils high, and you know your distance is 1000 yards. Using math you can determine the height of the target, in this case the bear is 72 inches high (6 ft) on his hind legs. You can may determine the distance through a) known distance marker on the ground b) laser type measuring device, or c) range finding reticles (which have short lines that mark mill angles). Formulas are taught in our Advanced Rifle Classes.
WIND CALCULATIONS: The Mildot Scopes can be used to compensate for wind drift. The best part of this is “NO MATH”!!!!!!
Since you have your scope sighted in and know the hits are right in the center, you can shoot by “side alignment” using the dots left or right of the reticle Bullseye. If a shot hits 1 inch left of the intended strike area, you can hold a Mildot on the left side of the Bullseye, and that becomes the new Bullseye, thus no scope adjustment and no math. It’s fast, which may be required if the Bear is ready to run. Of course the strength of the wind and your distance from the Bear are factors you must consider when determining how many Mildots to hold left or right.
GRAVITY: Using the same concept above, you can compensate rapidly for bullet drop without the need to adjust the scope or using math. You have your scope sighted in at known distances, and the vertical lines help you for the quick shot without making elevation adjustments on the scope itself.
Well, that’s MILDOT knowledge in a nutshell. See you in class.