Basics of the One-Mile Shot

Cartridges, rifles, optics, accessories— what’s needed for that way-out-yonder longshot!

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Twenty years ago or so, the idea of hitting a man-sized target at a mile (1760 yards) was the stuff of legend. Yes, there were historical precedents, such as Union sniper Captain John T. Metcalf, US Army Corps of Engineers, who in 1864, reputedly shot a Confederate officer at a range of 1666 meters (previously measured with a surveyor’s transit) using a heavy .50-caliber scoped muzzleloading rifle, and Carlos Hathcock’s 2000-yard plus kill during the Vietnam conflict with a single shot from a .50BMG M2, but these were considered rare events done by almost superhuman marksmen and perhaps assisted by a bit of luck. Today, however, guns, cartridges, scopes and more have enabled consistently accurate riflery at 1500 yards and much more. In Iraq and Afghanistan, for example, American soldiers with the .50BMG Barrett M107 have made more shots of that type than can be recorded.

long-range-bullets.jpgInterest in such shooting is not just academic, or limited only to combat environments overseas. Maximizing the security of American airports, seaports, power plants, stateside military bases, strategic industrial installations, border areas and more, involves expanding the perimeter of protection as much as possible. A rifle capable of engaging and nullifying vehicle-borne threats at distances out to 2000 yards and beyond is, thus, an increasingly important tool in dealing with potential terrorist attacks in the homeland.

Although the one-mile shot is no longer a once-in-a-lifetime event, it’s not something that one can do with a factory .30-06 hunting rifle and a 3-9x scope. Consistently hitting a man-size target at 1700 yards or more requires a special combination of cartridge, rifle, optics and accessories.

Cartridges
Perhaps the single most important factor in achieving consistent long-range accuracy is the selection of the proper cartridge. Generally, any cartridge for shooting at a mile or more should be capable of keeping its bullet above the speed of sound (around 1130 fps [feet per second] at 70 degrees Fahrenheit) at that distance. This, in turn, requires two things: a relatively high muzzle velocity of at least 2800 to 2900 fps, and a sharp-pointed, boattail match-type bullet having a high ballistic coefficient (BC).

Ballistic coefficient is a measure of how efficiently the bullet flies though the air. The higher the BC, the lower the drop, wind deflection and deceleration at any distance there is. High BC and high muzzle velocity combine to make range and windage estimation less critical. As a rule of thumb, any bullet for ultra-long-range shooting should have a BC of at least 0.650, and 0.700 to 0.800 (and higher) is better.

At present there are only a few production cartridges really suitable for military or law-enforcement shooting at 1700 to 2000 yards: the .338 Lapua, .338 Xtreme Tactical, .375 and .408 CheyTac, .416 Barrett and the .50BMG. There are also some wildcat, proprietary or limited-production cartridges that may be suitable. The cartridges I listed, however, are widely available, factory pressure-tested with proven ballistic performance.

No 6.5mm, 7mm or .30-caliber magnums are included on my rather short list of one-mile sureshots; .338 is pretty much the minimum caliber for such work. There are two reasons for this. First, only a handful of bullets in these smaller diameters have the requisite high BCs of 0.700 and above. For technical reasons, the larger the bullet diameter, the higher the BC that is realistically achievable in a practical bullet design. Second, tactical shooters want the bullet to do something useful when it hits, and relatively light, small-diameter bullets have limited capabilities in this area. Even the 240-grain .30 caliber Sierra with a BC of 0.711, at a muzzle velocity of 3000 fps, has only 759 fpe (foot-pounds of energy) left at 1760 yards, which is about as much as a stiff .357Mag load out of a handgun. While this may injure unarmored enemy personnel, it probably won’t reliably penetrate a flak jacket, car body or building wall. In comparison, the cartridges on my list have anywhere from 1000 to 3800 fpe of remaining energy at that distance.

Cartridges for the one-mile shot should also exhibit high ballistic uniformity. A variance in muzzle velocity of 35 fps (2850 fps and 2885 fps) with the 300-grain .338 Sierra MatchKing yields a difference in drop of nearly a yard at a mile, enough to undershoot or overshoot an enemy sniper in a window. Velocity variations in the teens or single digits are best.

Rifles
Accuracy is clearly the prime requirement for any rifle to be used for ultra-long-range shooting. A man-size target 18 inches wide, at one mile is almost exactly 1-MOA (minute of angle) in size, so 1-MOA is the minimum precision required. Actually, given the variables of shooter skill, gun steadiness, wind and so forth, a level of accuracy of 1/2- to 3/4-MOA at 1700 to 2000 yards is a more realistic minimum.

Though there are some self-loaders suitable for one-mile riflery, such as the Barrett .50 and Bushmaster’s new .338 Lapua Mag rifle, bolt actions are generally preferred because of their inherent accuracy, strength and reliability. The greater size of long-range rounds requires larger-than-normal actions, usually with diameters of 1.45 to 1.6 inches, and with larger bolts having beefier lugs. Barrels also tend to be hefty, as well as fairly long, 26 to 30 inches, to take full advantage of the heavy powder charges used in long-range cartridges. Muzzle brakes are common to cut recoil and allow lower gun weight. Suppressors are also widely used; though they don’t eliminate the supersonic crack of the bullet, they do reduce ground signature and muffle the muzzle blast, preventing easy detection of the shooter’s position.

Stocks for ultra-long-range rifles are most commonly of synthetic materials (fiberglass, Kevlar, graphite, etc.) and, more recently, aluminum. These materials are durable and strong, and unlike wood, are unaffected by water, solvents or changes in temperature or humidity. Increasingly in demand are modular aluminum stocks, such as the MODSS (Modular Stock System) from McRee’s Precision with interchangeable subunits, adjustments for height and pull length, multiple provisions for mounting lights, bipods/monopods, night vision devices and other accessories and a folding buttstock option. Such stocks can be easily reconfigured to meet changing operational requirements.

There is actually a pretty good selection of rifles suitable for ultra-range work. In .338 Lapua Mag, models include the Accuracy International AWSM, ArmaLite AR-30, Barrett M98B, Blaser 93 Tactical, Dakota Longbow T-76, FN PGM, Sako TRG-42, and Surgeon XL, as well as semi-autos from Bushmaster (which makes self-loaders in .338 Lapua, .375 and .408 CheyTac, and .505 Gibbs). The other major option in .338 caliber is the powerful .338 Xtreme Tactical, capable of 2000+yard accuracy.

A step up in bullet diameter are the Model 200 and 310 CheyTac rifles, in .375 and .408 CheyTac cartridges as well as the rifles, and then there’s the Barrett Model 99 in .416 Barrett. And in .50 BMG, there are quite a few choices for tactical shooters, including models from Accuracy International, Barrett (both semi-auto and bolt-action models), McMillan, Robar, Steyr and others.

Optics
Optics for one-mile shooting must be clear with low distortion and lots of light transmission. Preferred are variable-power models having a maximum magnification of at least 14-16x, and better 20x; variables allow the option of lower scope magnifications to scan a broad area to engage closer-range targets, or to reduce the effects of mirage. Powers of 30-40x and higher are not as popular, as they often come at the cost of smaller exit pupil size, less eye relief, and a decreased range of reticle adjustment.

Ultra-long-range scopes must be exceptionally rugged to withstand the recoil of powerful cartridges, and also must have a wide range of windage and elevation adjustments (up to 100 minutes or better on some models) to accommodate bullet drop and wind deflection at ranges approaching 2000 yards. Note that just about all scopes on long-range rifles are mounted on Picatinny rails having a 20- to 40-minute forward angle. The range of reticle adjustment increases with main tube size, which is why 30mm or larger tubes are preferred. Most commonly, click values are either 1/4-MOA or 1/10-milliradian (mil), at one-mile, these values are equal to 4.4 and 6.3 inches of bullet impact per click, respectively.

Reticle design is critical. Thick crosshairs will often obscure the target and fine crosshairs will be hard to see under reduced-light conditions. Almost all scopes for long-range work have reticles with some sort of rangefinding and/or drop compensation capability. In some scopes, this takes the form of circles or spaced lines designed to encompass 18 inches at various ranges, as well as a series of horizontal lines representing the aiming points for different yardages. The most common rangefinding system is the mil-dot reticle, which features round (Army) or oval (Marine Corps) dots that subtend either 0.20- or 0.25-mil and are spaced one-mil apart. Using simple mathematical formulas, or a device such as the Mil-Dot Master, such reticles permit fairly precise range and holdover/holdoff calculations. Scopes with mil-dot reticles are used by the US Marine Corps, US Army and other military organizations.

Reticles are placed in either the first or second focal plane. In the first focal plane, the reticle grows larger as the scope magnification is increased, while in second-focal-plane designs (what most Americans are used to), the reticle stays the same apparent size throughout the magnification range. With second-focal-plane scopes having range-finding reticles, such as the mil-dot design, the scope must be dialed to a specific magnification for the reticle to give accurate readings. On the other hand, a mil-dot reticle on a first-focal-plane scope can be used at any magnification, though the increasing reticle size may obscure part of the target at high magnification.

Although some contemporary “tactical” scopes feature mil-dot reticles and 1/4-MOA adjustments, many real-world professional feel that a mil-dot reticle is best used with mil click adjustments.

Only a few scope brands are found with any regularity on real-world long-range rifles here and abroad: Horus, IOR Valdada, Kahles, Leupold Mark 4, Nightforce NXS, Schmidt & Bender, US Optics and Zeiss.

Accessories
A shooter armed with a scoped rifle can make the one-mile shot, better ultra-long-range performance can be achieved with the proper shooting accessories.

Precise determination of the distance to the target is critical to accuracy, as an error in range estimation of only 25 yards at one mile can mean a difference in vertical impact of around 3 to 4 feet, more than enough to miss a target. While rangefinding reticles can get a shooter in the general ballpark, laser rangefinders give a precise measurement (plus or minus 1 yard) to the target. Models that can range out to 1500 yards include the ATN Ranger, Swarovski Laser Guide 8×30, as well as numerous models from Bushnell, Leupold and Newcon. For ranging to 2000 and beyond, Newcon is pretty much it with four models for military, marine, surveying and other purposes.

Some laser rangefinder models also include an inclinometer, compass, separate operating modes for different operating conditions and the ability to measure target speed. Note that laser rangefinders often don’t work well when the target is small or low in contrast with the background, or when there is fog or rain.

Even when the exact range to the target is known, a variety of atmospheric factors can greatly influence bullet trajectory. Precise knowledge of such conditions can be achieved using portable weather stations. The simplest of these measure wind speed and temperature only while more sophisticated instruments, such as the top-of-the-line Kestrel 4500 indicate wind speed, temperature, pressure, humidity, time/date, altitude, and the angle of the prevailing wind to the target, which can calculate the effective wind value. However, since these devices only register conditions at the firing point, they don’t reveal if there are different conditions further downrange, almost a certainty when the target is a mile or more away.

Tactical shooters often fire from the top of a building or the side of a hill or mountain. Even relatively small angles up or down can require sizable trajectory adjustments at one mile. Inclinometers, such as the Angle Cosine Indicator from Sniper Tools Design Company LLC, are useful devices for such shooting, as they attach to the rifle and give the shooting angle of the rifle. More importantly, the ACI also gives the proper adjustment factor that, when multiplied by the straight-line range to the target, gives the effective range for proper holdover estimations. Some of the better laser rangefinders also have an inclinometer feature.

Proper rifle support is a must. When shooting off sandbags is not possible, bipods are universally employed. There are a number of good bipods, Parker-Hale, Versa-Pod and more, but the most common seems to be the ubiquitous Harris design, which has stood the tests of both time and extreme conditions.

Rifle cant is an often undiagnosed cause of lateral dispersion at extended range. As little as one-degree, an angle many shooters find difficult to discern, can produce 0.5 of an inch of dispersion at 100 yards. A number of devices are available to combat this problem, ranging from simple bubble levels that mount on the scope or Picatinny rail, to electronic devices such as the Deros Level Grouse that use lights to indicate when the rifle is not vertical. Devices such as the Level Grouse can be perceived in the peripheral vision while aiming through a scope, and thus have advantages over bubble levels, which require a shift in visual focus from the crosshairs.

Finally, precision shooters are increasingly coming to rely upon ballistic calculators, such as Barrett’s BORS, CheyTac’s ABC (Advanced Ballistic Calculator) and CABC (Civilian Advanced Ballistic Calculator) and the Horus Vision Sighting System. A relatively new development, these devices allow the inputting or selection of a wide range of data, such as cartridge, bullet velocity and BC, target distance, atmospheric conditions, altitude and shooting angle, and so forth, which are used to yield trajectory information via an interface with preprogrammed ballistic software.

Different calculators offer different features. For example, the Horus system integrates a unique rangefinding reticle, inputs from a Kestrel wind meter and ballistic software on a handheld PDA to yield click adjustments intended to place the first shot on target. The Barrett BORS, on the other hand, is a ballistic computer that mounts on the scope and engages the elevation turret, allowing the BORS unit to register each elevation click. As elevation clicks are dialed in. The unit automatically adjusts up/down angle shooting, and variations in temperature and air pressure. The unit is preprogrammed for the trajectories of several popular cartridges, but an interface with Barrett ballistic software allows the unit to be programmed for other ammunition.

Finally, the CheyTac ABC and CABC likewise combine data from portable weather stations and laser rangefinders with software on a PDA having preprogrammed radar-derived ballistics for all military sniping ammunition (as well as several other popular cartridges). Though they all function in unique ways, these ballistic calculators have the same purpose of enabling the shooter to confidently fire with the expectation of a first-round hit.

Final Notes
That about covers the basics of the equipment needed for making successful shots at a mile or more. That’s not the whole story, though. Most important of all is skill. Even with a 1/2-MOA rifle, high-magnification optics, laser rangefinder, ballistic calculator and more, a precision rifleman still needs superior shooting technique to achieve consistent hits at one mile or more. Moreover, technological gizmos can break if dropped or when subjected to adverse conditions; their batteries can go dead; and sometimes they just don’t work properly.

The well-schooled long-range shooter not only knows how to shoot, but is also skilled at range estimation, wind reading, and proper trajectory compensation for different atmospheric conditions, shooting angles and target speeds. And such skill cannot be taught, it must be learned through extensive study and practice.

All that is perhaps why there is still, quite deservedly, a mystique about the one-mile shot.


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  • TheTopMostDog

    I’ll do it one day.

  • Vic

    I had the chance to fire my new Remington XCR tactical long range .300 win mag. rifle on 05DEC09, at a long range impact zone. The conditions were 130 feet above sea level, 40-42 F and the wind was at full value north to south my right to left, Firing from the prone position shooting off hand with my left.
    Using PMC’s 300 XLA 150 Gr. XLC-BULLET HP with a Leupold Mark 4 LRT, 6.5-20×50 scope. I fired the rifle 2,534.716 meters or 2,772.0 yards (approx. 1.575 miles) with a 7-8 second flight time. 2 out of 3 were confirmed hits on target and 4 out of 5 on a later date with 165 Gr. Nosler Ballistic Tips.
    I was doing all of this on the fly with just using the mil-dot system. Watching how the winds were shifting, affecting the tree tops and vegetation from my firing position, mid way and at target location. Confirmation of range at first was confirmed with a 1:50,000 Military installation map(we all know how accurate them maps really are) and then later an (LRAS)was used for an exact range reading and confirmation.
    All of this can be achieved with lots and lots of practice and lets just say 4,000+ rounds later.

  • Aim and Squize

    Any commits for the 300 rem ultra mag?