Monday, October 17, 2011


No matter if you’re packing a poodle shooter or a real rifle, getting a hit at long range requires accurate range estimation, which has traditionally been one of the hardest things for a solider or hunter to learn.

It goes back to ballistics why this is all so important at ranges beyond your battle sight zero, ranges which are being encountered every day in Afghanistan where the average engagement range in the hinterlands is 500 meters.

Even being 50 meters off on your estimate makes a big difference when you get to shooting “way out past Fort Mudge”, as Jeff Cooper would say. Say you’re shooting a .308 at a target you estimate to be at 400 meters, but it’s actually 450 meters. Due to that seemingly small error, your trajectory at the target will be a full foot lower than your aim point. Still close enough for minute-of-badguy (shoot him in the nards) but not close enough for a shot into the vitals of a deer.

Further out, estimating a 650 meter target to be 600 meters, you’ll be shooting two feet low. A fifty meter error at 800 yards is a 32-inch difference in your bullet’s trajectory.

As Dirty Harry says, “A man’s got to know his limitations.” Which is why I consider myself perhaps a designated marksman; I don’t shoot over 600 meters and that’s the limit of the BDC on both my scopes anyway. I might try a 700 meter shot with hold-over in an emergency, but that would be the absolute max.

At those ranges, a real sniper, which I’m not, with a real sniper rifle, which I don’t have, is just coming into his own. I leave that to the experts. I’m not that guy who wants to “make a 1,000-meter shot so I’ll look cool on the Internet”.

Nowadays, we have very affordable and compact laser rangefinders as well as the Mil-Dot system in some optics. But let’s say you don’t have a scope with Mil-Dots because you’re not a sniper type. Neither do you have a laser rangefinder. Or the battery in you rangefinder goes dead in the cold or you drop the thing down a scree slope into a creek or the darn thing just stops working.

I had a GPS for all of two weeks. I accidentally dropped it on a gravel road once and it never worked again. Good thing I wasn’t five miles back in the mountains and depending on the thing to get me home. As for myself, I have always been adept at land navigation via map and compass, especially terrain association here in the mountains. I’m weird enough that I look at topo maps and Google Earth for fun, finding good places to hunt or places to explore deep within my warped little brain.

If you’re good at land navigation, a map can be right handy to estimate range pretty close. Here’s what I mean with the following example.

Your position is in the center of the black circle as you sneak through the low point of the saddle in the ridge to take a peek at the country beyond. You see Bruno the Great Wapiti come ambling out of the woodline down by the creek bottom, the middle of the red square. With a piece of paper or any straight edge you can put a mark on, you measure the distance from the circle to the square and then slid your straight edge down to the distance scale at the corner of your map and measure it. The blue line represents this. So, ol’ Bruno is about 800 meters away, too far for a shot.

The most common unaided eyeball method of range estimation is the “Unit of Measure” method, which was the first one taught when I was in the service, going on the theory that every red-blooded American boy should have been on a football field and know how long it looks. One hundred meters is a football field with both end zones included.

100-Meter-Unit-of-Measure Method. To use this method the sniper team must be able to visualize a distance of 100 meters on the ground. For ranges up to 500 meters, the team determines the number of 100-meter increments between the two objects it wishes to measure. Beyond 500 meters, it must select a point halfway to the object and determine the number of 100-meter increments to the halfway point, then double it to find the range to the object.




The target—Its clearness of outline and details.

When most of the target is visible and offers a clear outline.

When only a small part of the target is visible or is small in relation to its surroundings.

Nature of the terrain or position of the observer.

When looking across a depression, most of which is hidden from view.

When looking across a depression, all of which is in view.

When looking downward from high ground.

When looking upward from low ground.

When looking down a straight, open road or along a railroad track.

When field of view is narrowly confined, as in city streets, draws, or forest trails.

Light and atmosphere

When looking over uniform surfaces like water, snow, desert or farm fields. In bright light or when the sun is shining from behind the observer.

In poor light such as dawn and dusk; in rain, snow, or fog, or when the sun is in the observer’s eyes.

When the target is in sharp contrast with the background or is silhouetted by reason of size, shape, or color.

When the target blends into the background or terrain.

When seen in the clear atmosphere of high altitude.

The British and former Commonwealth nations still use the appearance method. And have been doing so for a long time. I first became aware of it from an episode of Sharpe’s. It’s mentioned in American manuals, but it’s vague as hell and doesn’t sound too useful, not made simple and easy like the Canadian Army example below.

The appearance method compares the way an object looks at 100 metres and at greater distances. By comparing the appearance of a man in several positions—at 100, 200, 300, 400 and 500 metres—observers can establish a series of mental pictures. They will find that, as distances increase, a man's figure becomes smaller, his outline becomes increasingly blurred and his other features gradually fade out. The following may be used as a rough guide to determine the distance a soldier is from the observer:

a. 200 metres—all parts of the body are distinct;

b. 300 metres—outline of the face becomes blurred;

c. 400 metres—outline of the body remains, but the face is difficult to distinguish;

d. 500 metres—the body appears to taper from the shoulders; movement of the limbs can be observed;

e. 600 metres—the head appears as a dot with body details invisible and tapering noticeably.

That’s pretty easy to remember with some practice. In the same way, the appearance of other familiar objects can be learned. For instance, I know if I can no longer see Ben’s willy, he is beyond 500 meters.

This is from the 1942 Red Army sniper manual, but I don’t find it very useful. I mean “400-1000” meters or “8-11 klicks” is not real precise.

Something else I never heard mentioned, except at an Appleseed shoot, is the use of the front sight of your M1/M14 to measure range fast and easy for the average rifleman. If the body of the target is as wide or wider than your front sight post, he is within your 250 meter battle sight zero and you don’t even have to worry about elevation, just hold center mass and shoot.

The Brits took this method a step further, using the front sight blade of the Lee-Enfield rifle to help measure range.

You can figure out the same thing for your own rifle, whether using open sights or a scope. I placed man-size silhouette targets at known distances in 100 meter intervals then move around sighting in on them. You may find, for instance, that the small part of a duplex crosshair up from the horizontal wire is the height of a standing man at 100 meters or that the thick portion of a duplex reticle covers the width of a man-sized target at 300 meters, or whatever. It’s something you have to figure out in practice not in theory.

I was lucky with my German Hensoldt Z24 scope on my FAL, as it has a goofy multi-line vertical post reticule. I figured out how many lines were needed to span the width of a silhouette target at what ranges.

I don’t have a manual for my old Z24 Zielfernrohr fur Sturmgewehr (1 each), and my German isn’t good enough to be of much help if I did, but I have found that at 300 yards, a man-sized silhouette fills all the pointer lines. At 500 yards, a silhouette fills three of the lines.

For quite some time, a common military method used in range estimation was averaging. Every man in the squad estimated the range to the target and the total was averaged. This can provide a more accurate estimation, but only if the individuals at least generally know what the hell they are doing.

One should know one’s own pace count, the average number of steps required to cover 100 meters, counting each time the left foot hits the ground. Mine is 65, and pacing distances to place targets I find, upon verifying with the range-finder, I am almost inevitably within 10 meters of the desired distance.

With a pace count, in a static position, you can figure ranges with a pretty decent amount of accuracy. Of course, this method won’t work too well in a tactical situation. At any rate, you can pace out the ranges to various landmarks in your field of fire, and these landmarks provide “key ranges” from which you can much more easily estimate the range of any target which appears in the vicinity. I’ve used this hunting before, pacing and marking and then setting up on a good vantage point well before dusk to wait for the deer to come out.

Something I’ve always used is what I call the fenceline method. Growing up on a farm and in farming country, I kind of take for granted the size of a piece of land; quarter section, half section etc. Fenceline to fenceline on a quarter section field is exactly a quarter mile, or 440 yards. For the half sections it’s a half mile or 880 yards.

I have heard often of knowing the standardized distance between telephone or powerline poles, which is pretty much the same thing. It does work pretty well, where such things are present. I used it on antelope once by counting highline poles. If the target is in between the fencelines or power pylons, the bracketing method can be used.

Bracketing. If the target is known to be located between two reference points of known distance then the bracketing method may be used. Simply add the two known distances (X and Y) and then
halve the sum for a close approximation of the range. For example, if X is 1000 metres and Y is 600 metres, the sum is 1600 metres, halved is 800 metres, which is the range. The further away the
target, the larger the bracket should be.

Obviously, if the target is visibly closer to X than to Y you would have to take that into account to get a more accurate fix, using more the key range method.

Here’s a few handy methods you can use if you have the distinct displeasure of someone shooting at your ass.


Since sound travels through the air at a fairly constant speed (330 metres per second), it is possible to estimate the distance from a weapon that has been fired if the traveling time of the sound from the weapon is known. The traveling time is the period between observation of a muzzle flash, backblast, smoke or dust raised by the concussion and hearing the round being fired. The time can be measured accurately by counting at a rate of three beats per second during the period. Counting starts as soon as the visual effects of the weapon firing are observed and cease when the report of the weapon is heard. The number reached will be the approximate distance to the
weapon in hundreds of metres. If the count of eight has been reached when the report is heard, the distance to the weapon is approximately 800 metres.


(No, crack and thump does not relate to being constipated in the field.)

When a bullet passes near, one hears two noises: first, the crack of the bullet passing, then the thump of the weapon being fired. The crack is heard before the thump because the bullet travels faster than sound. The thump indicates the direction of the weapon. The distance to the weapon can be estimated by timing the interval between the crack and the thump. The further away the weapon, the longer the interval between the crack and the thump. The time between the crack and thump at the following ranges is:

a. 300 metres — 2/3 of a second;

b. 600 metres — 1 1/3 seconds; and

c. 900 metres — 2 seconds.

If it only takes a quarter of a second, you’d better have bayonet your bayonet already fixed.

Undoubtedly the least desirable method of range-finding is the bullet hole technique. This comes into play when someone is not just shooting at your ass, but coming real close to outright hitting it.

After an enemy bullet parts your hair, you can find the bullet hole, hopefully in a wall or the dirt rather than your buddy’s head, and insert a pencil, stick, section of cleaning rod, etc. into the hole. The stick, of course, points straight back at the shooter. You either visually use the stick to determine the correct direction of the enemy or, better yet, stay hunkered down under cover and shoot an azimuth of the direction with a compass or GPS.

Then you can use the angle at which the bullet struck to get a rough estimation of the distance from which your opponent is firing. I got these angles using a ballistics graph of a 7.62x54R 174-grain heavy ball round’s trajectory, assuming some goat-smelling jihadist is firing at you with an SVD, PKM, Mosin, etc.

So, an example. You and your partner are sitting in the old barn marked “A”, minding your own business, warm and dry for once, and observing traffic on the road across the creek. Then a bullet whips past your head and into the wall behind you. Of course the first thing you do is hit the deck and stay there and say a bunch of bad words. After the cussing, you crawl over to the bullet hole, put a pencil in it, the angle of which indicates a 400-500 meter shot. Then you get a compass azimuth of 38-degrees (just an example: I’m not going into back azimuths and magnetic declination today) from the direction the pencil is pointing.

With the direction and distance plotted out, you can figure out on the map that the little bastard who took a potshot at you is probably up in the trees on that finger spur marked “B”. You can do roughly the same thing by Mk. I Eyeball, provided you don’t stick your head out to do so. At any rate, you have a pretty good idea where he’s at now so you can move to better cover and/or concealment to start glassing the area to find him.

I am very happy to say I’ve never had to make use of this method, although one time a nice mule deer buck tried to lay down fire on me with an old Russian Goryunov machine gun. But that’s a whole other story.


jollyrogers said...

You mentioned power poles in your reference of "standardized distances".

If you are going to use this method keep in mind there is a difference between "transmission" and "distribution" lines.

Transmission lines are the ones that you may see on metal towers, H-frame supports, or 60+ ft poles. These are the ones that carry elec from 23,000V to 365,000V; they may sound like they "hum" when you are close to them.

Distribution poles are the ones that carry between 5,000V and 14,000V. You will see transformers on these poles which drop the voltage down to what we like to see in our homes: 120/240V.

My point is not to give an exposition on power line construction, it is just that there are different distances that each type are typically spaced.

Here the local electric companies typically do not run more than 375-380 feet as a maximum distance with their distribution poles. Especially if the poles are in the 40-45 ft height range, or if all wires are on or above the cross-arms.

If the lines are on 35-40 ft poles or if the lines are attached in a vertical arrangement (one over the other) the distance will run closer to the 300-335 ft between poles. This distance is often seen on lines cutting through farm fields.

I use this a lot in MI for work and hunting.

I can already hear someone belly aching about not knowing how tall a pole is. If the pole isn't half rotted, look at the pole and look for a brand around eye level. Look for a number like 45-5 (45 indicates total pole length, has to do with pole "class" or diameter). A 40-4 or 4-40 indicates a 40 ft pole.

On most days, you could probably care less. But if you need it, it can help.

Bawb said...

Thanks for the information; you obviously know your stuff.

I hunt three places where there are, from your description, obviously transmission lines. All are different styles with different distances in between. I either pace counted the distance between or, now, use the laser rangefinder. I guess I kind of assumed folks would know to check the distances when the types of lines were different.

You mentioned hunting in MI. Are you a Yooper or a Troll? When I was up in the Arrowhead country of Minnesota, the guys with the patience to just sit along a powerline cut and wait always got their deer, while the guys who drove the backroads for hours or days mostly had to just get lucky. That area was pretty similar to da UP, eh, but I've never been around southern MI and don't know what kind of country that is.

jollyrogers said...

I would be of the Troll variety. Spent a winter up in the Keweenaw Peninsula...400+ inches of snow in less than 6 months just didn't do it for me.

Would love to spend more time up there than I do. Some spots look like artic tundra (and nearly as cold). Need to have a season for mosquito though. Only place with larger ones is Alaska I think.

Under the bridge varies. I sit roughly in the middle of the mitten. South-East of here tends to be flat and swampy. West of here are rolling hills with a lot of timber still. Both offer good bucks.

As you head up toward the bridge there is a lot of 2nd generation forests - mostly pines that replaced harvested hardwoods. Bucks run a little thinner.

As for your observations in MN, they are true here as well. Figure a 300 ft wide path cut for unending miles offers a lot of forage for turkey, pheasant - which also brings in fox, coyote, and cougar (which don't really exist) - and deer. So if your season is coming to a close and you still have space in the freezer...

Bawb said...

Actually, our month-and-a-half bow season just ended and our big game rifle season is just beginning, but that is only a mere 5 weeks long;) Although I do have a special late season bow tag that runs into January.

Being a military gun nut, I've already scored with a Mauser, Lee-Enfield, Springfield and Garand, so this year I'm hunting with a scoped FAL....just to prove that an Evil Black Rifle does indeed have a "legitimate sporting purpose".