## The Story Of Mil Dots

Spec Ops Shooting

Get Instant Access

Remember those World War II submarine movies where the captain ranged an enemy ship through his periscope? Actually, he was measuring the ship's length in mils—and since whole classes of ships were built to the same dimensions, he already knew its length in yards. Thus, in the same way we range today with a mil dot reticle, he could range that ship, then accurately launch torpedoes to intercept it. This mil system for ranging goes back at least to World War I, when artillery forward observers used the mil scale in binoculars to adjust artillery fire. The problem is that binoculars and periscopes use 10-mil increments—equaling 10 yards at 1,000 yards—much too large for ranging man-size objects.

In the late 1970s, U.S. Marine Corps Capt. Jack C. Cuddy was challenged to find a more exact way for Marine snipers to estimate range. After experimenting with various ways to use the mil system in a rifle scope, Cuddy settled on the system we see today, found not just in the USMC's 10x Unertl but in many other scopes all around the world. Despite the development of laser rangefinders, the mil dot reticle remains the sniper's mainstay because it adds no moving parts or bulk or weight to his scope, and it's unaffected by weather, but it yields precise ranges unmatched by anything but a laser.

Yet mil-ranging inherently involves a bit of compromise. To reduce fractions and simplify calculations, the U.S. military says a 1-mil angular measurement equals 1-6400 of a circle. Actually, a circle contains 6,175 mils, which means the U.S. system accepts a 2 percent error, equating to 10 yards at 500 yards or 20 yards at 1,000 yards. The Russian mil measurement, too, is a compromise, but they round their circle down to 6,000 mils, causing a slightly larger error of about 3 percent.

USMC Capt. Jack C. Cuddy (R), developer of the mil dot reticle, speaks to Marine Corps Commandant Gen. Robert Barrow at the 1979 Interservice Rifle Championships.

Let's try a couple of examples.

Several blocks away, you spot an insurgent sniper atop a roof about to engage a friendly patrol. Through your mil dot reticle^ you see a light pole just below the hostile sniper. Being a complete professional, you know that this style of Iraqi light pole is 9 feet tall, which means 3 yards high. In your reticle, the pole measures 8 mils. Your spotter taps out the formula on a handheld calculator:

8 mils

= 375 yards

We'll try one more. This time while covertly observing the Baghdad Airport Highway, you detect a pair of electric wires running from a dog's carcass back to a low wall, behind which sits a man watching for an American convoy. Knowing that terrorists have used donkey and dog carcasses to conceal improvised explosive devices, you place your mil dot reticle on that wall—which is the same height as the wall where your team is hiding. The wall is 1 1/2 yards high. It measures 5 mils high. Again, your spotter taps it into the calculator as quick as you announce your readings:

Round mil dots in this Leupold Mark 4 LR scope have been etched into the first focal plane.

illustration, is actually 10 mils high and 10 mils wide, because the very center dot was left out— had it been there dead-center, it would have interfered with your aim. Notice that the crosshair intersection point is at the exact center of where this missing dot would have been. When counting mils, just pretend this dot is there and count it.

Also look carefully at where the chick stadia lines start on the reticle outer edges. Notice that instead of these outermost mils starting or stopping at the middle of a dot, they start/stop at the edge of a thick line. Therefore, you can see 10 mils of right/left width and 10 mils of up/down height.

### A Closer Look at Mil-Ranging

A mil dot reticle is a lot like a qualify rifle—it offers great precision, but it can be no more accurate than the man using it. To begin with, don't be casual about how you hold your rifle when mil-ranging. Aim the reticle just as steadily and as well supported as when you're using that reticle to take a shot.

Second, be precise when it comes to the object you're measuring, and I mean that two ways: both for knowing or estimating it's real dimensions in yards or meters, and how exactly you measure it in fractions of mils. Know that a

+2 0

## Hunting Mastery Selected Tips

Deer hunting is an interesting thing that reminds you of those golden old ages of 19th centuries, where a handsome hunk well equipped with all hunting material rides on horse searching for his target animal either for the purpose of displaying his masculine powers or for enticing and wooing his lady love.

Get My Free Ebook

### Responses

• bosco
What MILDOTS are for?
4 years ago