Sheffield Style Bowie

Spec Ops Shooting

Ultimate Firearms Training Guide

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long-range you can make 1ST ROUND hits at 1,000 yards.

Jacob Gottfredson

Complete reliance on ballistic software programs or drop tables shown on some manufacturer's cartridge boxes is a mistake if you wish to be a successful mid-, long-, or ultra longrange shooter as is extensive shooting at various distances in only one set of conditions.

Trajectory paths given by ballistic software require the input of velocity, bullet weight, ballistic coefficient, height of center-of-scope to center-of-bore, and environmental conditions to include temperature and barometric pressure. Inherent in that however, is the often mistaken assumption the data is correct. In reality it seldom is. For starters, the software assumes every bullet and every velocity is identical, which they are not.

Bullet weight, center-of-form vs. center-of-gravity, and consequently ballistic coefficient vary even within the same lot of bullets. With the exception of those programs that take into account the change in ballistic coefficient with changing velocity as with Sierra's, the program assumes the same ballistic coefficient throughout the bullet's flight. Velocity is not a constant either, but varies with each shot however small you might make velocity spread by careful handloading and testing.

If all that isn't enough, simple statistical variation as pointed out by Craighton Audette's extensive testing, as well as my own (see Precision Shooting Annuals), shows shots sometimes go astray through pure happenstance. To be brief, an analysis method often used in manufacturing called Statistical Process Control Analysis is used to monitor the quality of production widgets. Let's assume our widget is an advertised 1/2-minute rifle. What the exact criteria is for such stellar performance is unknown. To test such a claim, however, we set our upper and lower control limits about 0 as indicating 1/2". We set our lower control limit at .25" and .7" as our upper control limit. That is, some groups may be smaller than 1/2 minute and some larger.

Deros Level Grouse

Long range shooting requires precision. This rifle employs a Deros Level Grouse to help the shooter control cant. It is mounted on the left side of the scope, allowing a right-handed shooter to see level easily. If the shooter uses both eyes, the lights appear to be in the bottom of the scope's image. It blinks red if tipped to the right and green if tipped to the left. No lights blinking indicates the rifle is level.

Long range shooting requires precision. This rifle employs a Deros Level Grouse to help the shooter control cant. It is mounted on the left side of the scope, allowing a right-handed shooter to see level easily. If the shooter uses both eyes, the lights appear to be in the bottom of the scope's image. It blinks red if tipped to the right and green if tipped to the left. No lights blinking indicates the rifle is level.

As you shoot 5-round groups with all the perfect technique you can muster, and all else being equal, some groups might be smaller than 1/4 minute and some larger than .7". This seems reasonable, and we are not dissatisfied with the load or handload. We aren't unhappy if any groups fall below the 1/2 minute mark surely. However, there are techniques to show the process may be out of control. That is, although it appears to average the advertised 1/2 minute, it will sometimes not do so, and in fact may sometimes be quite a bit larger than a 1/2 minute. This process lets you understand the variability raising its ugly head while making a long-range shot. The same process can be used to evaluate the variability of the first shot's placement. It is important to know the probability of where the first shot from a cold-clean or cold-fouled barrel

Jacob Bynum of Rifles Only practices at 1,200 yards with one of Gottfredson's long-range rifles. Geiges built the rifle with both 6.5x284 and .308 Baer Kreiger barrels. The action is a Nesika with a Jewel trigger, mounted in a McMillan 1,000-yard benchrest stock. The scope is Nightforce's 5.5-22x50mm NSX. A Jet suppressor has been attached.

might hit as well as some number of follow up shots.

Let's assume again you are on your home range shooting under unchanging environmental conditions and a controlled technique from a bench or a steady prone position. You have perfectly loaded ammunition with single digit velocity spreads. You are satisfied — once sighted in — you can make a first round hit at 1,100 yards and your group would, for example, nail an elk in the kill zone four shots out of five tries. Great! Now let's change the environmental conditions. Your constant conditions might have been 60 degrees and 23.5 barometric pressure or 90 degrees and 29.95 barometric pressure or anything in between. Change either constant or both and all you have accomplished changes as well. Your sight in must change, the flight path changes, and consequently your come-ups must change as well.

How And Why

As barometric pressure decreases, the bullet's path is flatter, requiring fewer come-ups on your elevation dial. As temperature decreases, the bullet's path may be less flat and the muzzle velocity reduced. Reticle designers and theorists David Tubb and Brand Cole have included density/altitude charts within the image field of their scopes to help you figure this out. However, the chart is dependent on bullet configuration and muzzle velocity to arrive at the necessary come-up changes. They have done this for incline shots and devised elegant rangefinding techniques within the scope's image field as well.

But again, these are guides only and take considerable practice to use effectively. The same thing can be accomplished using ballistic software by developing both an at-home sight in and ballistic path and a field sight in and new ballistic path for the new conditions you might hunt in. Carrying a pocket PC helps tweak all this as does a Kestral or similar instrument in the field. But again, this is all predicated on absolutes as described above. Although great guides, they are only the best guesses modern mathematics can provide.

Given all the bad news given thus far, there is even another culprit laying in wait to take its toll on first-round hits at long range. Once the bullet exits the barrel, it's on its own, and acts in very peculiar ways. One of them is spin drift, another phenomenon Tubb and Cole ingeniously included in their scope's reticle by sloping the vertical reticle slightly to the right as it proceeds down the wire. If you use hash marks for holdover vs. dialing to range, that slope takes care of spindrift for one bullet and muzzle velocity. It helps, certainly, but is no panacea.

In Flight

There are several other flight characteristics hiding in the bushes such as "lift." This tends to make the bullet go a bit higher in a right-to-left wind and down a bit in a left-to-right wind. At long range this can be considerable. A true head wind will force the bullet lower and conversely a tail wind will force it higher. Incline shots, either up or down, result in a high shot if the range from your eye to the target is used.

One last round of foreboding. Some days or times of the day present a turbulent atmosphere through which seeing a target at long range is difficult. However, a clear atmosphere with some mirage is perfect, allowing you some understanding of the wind's fickle nature.

Are first round hits beginning to seem impossible? Let me clarify range. I have read articles with Long Range in the title, the subject of which were shots to 500 yards. This is actually considered mid range. Long range begins at 600 yards, extending to 1,200 yards, and ultra long range is anything past 1,200 yards. And each require appropriate equipment and skills. Are there answers to all this? Barring wind, the answer is yes.

A myriad of problems plague the long-range shooter and

1000 Yards 308 Winchester

Remember: "Light up, bullet up. Light down, bullet down." What this little reminder means is if you are shooting in cloudy conditions and the sun finally comes out, the bullets will go high due to how light affects your optics. Remember also a tail wind causes the bullet to go higher than a facing wind. Some have calculated this to be almost 4" at 1,000 yards with a .308 Winchester.

Remember: "Light up, bullet up. Light down, bullet down." What this little reminder means is if you are shooting in cloudy conditions and the sun finally comes out, the bullets will go high due to how light affects your optics. Remember also a tail wind causes the bullet to go higher than a facing wind. Some have calculated this to be almost 4" at 1,000 yards with a .308 Winchester.

Sheffield Bowie

many can be overcome if the shooter is willing to make some compromises and put in a little extra time. Barring unreadable wind, turbulent atmosphere, and other circumstances over which you have no control, first round hits at long-and ultra-long-range can be made.

Solutions

Faced with changing environmental and atmospheric conditions, velocity spread from one bullet to another, statistical anomalies, bullet flight characteristics, and poor visual acuity to name just a few, you must first choose the max range you wish to attempt and the appropriate equipment to make productive hits on his target at such range to overcome these bad actors.

To begin, let's assume you've found a promising lot of bullets, weighed them, possibly meplated them, and checked ogive placement and runout. You have prepped your cases and tuned the rifle to produce single digit velocity spreads with a bullet of high ballistic coefficient. Your scope and reticle is capable of fine precision at long range. You have practiced at your home range and gained confidence in your ability to make hits, to say, 1,500 yards. Great.

Now comes the easy part of all this, but also the reason I said it takes a bit of compromise and extra time. For example, let's assume you live on the coast. Standard conditions prevail at 59 degrees

Readjusting comeups from 60' elevation at home to 6,500' elevation in Wyoming. The top hit was made by Jacob's cousin, Steven, with Jacob's Armalite .50 BMG. The hit in the pink dot was shot with Jacob's 7mm RSAUMmagnum from Surgeon Rifles called the Surgeon Razor. The range is a few yards short of 1,000. (Jacob is the old man in the photo, by the way.) Comeups had to be adjusted down about 1.75 MOA.

Readjusting comeups from 60' elevation at home to 6,500' elevation in Wyoming. The top hit was made by Jacob's cousin, Steven, with Jacob's Armalite .50 BMG. The hit in the pink dot was shot with Jacob's 7mm RSAUMmagnum from Surgeon Rifles called the Surgeon Razor. The range is a few yards short of 1,000. (Jacob is the old man in the photo, by the way.) Comeups had to be adjusted down about 1.75 MOA.

F, 29.53 barometric pressure, 0 elevation or nearly so, and relative humidity of 78 percent. You might be a military longrange precision shooter or hunter and travel to a location where environmental conditions are significantly different than on your home range where you put in all that effort.

Let's assume you are now faced with 30 degrees F in the morning at 8,000' elevation with a barometric pressure of 22.5 and humidity of 35 percent. In the afternoon the temperature rises to 65 degrees. If you don't intend to reload at your location, the humidity can be disregarded. If you reload at your location, humidity will alter weighing powder a bit, and you may need to retune the load. That's a good idea since your home load may not be tuned in such different conditions.

Before making a shot, you pull from your pack a Kestrel or some equivalent instrumentation to monitor environmental conditions, sheets you've printed from a ballistic software program at various altitudes and temperatures, and a wind flag or two. Note I have changed from "elevation" to "altitude." I did so because your primary focus is on barometric pressure, not elevation. You might camp in a spot at 8,000' for days, over which you will note barometric pressure changes slightly, and barometric pressure affects the bullet's flight, not elevation. For those of you who refuse or can't obtain ballistic software, Ballisticards can be custom produced for your ammo at various combinations of environmental conditions. They are plastic coated and easily carried.

Your first guess is muzzle velocity may not be the same as it was on your

Barrett 416 Ammo

Practicing at 1 mile with a Barrett .416 fitted with a BORS computer. It monitors temperature and barometric pressure constantly. The shooter ranges the target, then turns the elevation dial until that range appears in the view window and voilà!

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Practicing at 1 mile with a Barrett .416 fitted with a BORS computer. It monitors temperature and barometric pressure constantly. The shooter ranges the target, then turns the elevation dial until that range appears in the view window and voilà!

home range. Some over zealous types take a chronograph along. You might also take along some sheets that give you information about density, altitude and the like from David Tubb and Brand Cole.

With all this gear in tow, find a place much like you intend to shoot. If guarding a hill in Afghanistan you have a ready practice location. If a hunter, you might want to find a place much like you intend to hunt, but not in the same area. You don't want the animals in your hunting area running to the next county. Starting at 600 yards, place steel targets spray-painted white at various ranges to 1,500 yards or a mile, or you might want to spray paint 12" bulls eyes on large boulders in the area. I generally film shots because it is often difficult to see a hit at such ranges, particularly if you are alone, unless you have a lot of heavy LaRue mechanical reactive targets. The camera lets you know without walking to every target.

While doing all this, you have kept constant watch on the wind, barometric pressure, clouds, lighting conditions, and temperature. Start in the morning and fire a 3-round group at the 600-yard target. In a data book you have brought for the purpose labeled with those headings, note the placement of the group in the data book along with the environmental conditions. When the group is in the 1-minute area and in the bull, note the comeups and wind change you had to make. Proceed to shoot similar groups at all the targets until you arrive at your long-range maximum. If you have brought several ballistic readouts

Expect this kind of elevation variability at long range when altitude changes are made. For example, the bottom group would be shot at sea level, the middle group at 6,000', and the top group at 8,500'. This change is due to decreased barometric pressure. At long and ultra long ranges, this could result in significant misses. White dots were added electronically to show bullet hits.

Expect this kind of elevation variability at long range when altitude changes are made. For example, the bottom group would be shot at sea level, the middle group at 6,000', and the top group at 8,500'. This change is due to decreased barometric pressure. At long and ultra long ranges, this could result in significant misses. White dots were added electronically to show bullet hits.

of different environmental conditions, pick the one that fits the best and make changes there. Doing this will allow you to know your limitations. Also note if your shooting position will allow you to hold 1 minute or less.

Do the same thing at noon and then in the afternoon, say at twilight when you feel there is a better chance of seeing your intended target. In this particular example, you will find to make hits your comeups at 1,000 yards may be about 1.75 MOA less than at your home range. At 1,000 yards, that is a 17.5" miss high if you used your home ballistic flight path.

When you locate to a new set of environmental conditions, you may find you can't duplicate your shots with consistency. Back off to a range where you can. You will also note during certain hours of the day, the atmosphere is turbulent, not allowing you the visual acuity to make such shots. Back off. If the wind is up, and the velocity of the wind is waning and waxing and switching, back off. If you can't hold much less than 1 MOA, back off. But there is yet another critical problem to consider.

Watch the mirage carefully. It is another valuable indicator of the wind. When it begins to impede visual acuity, however, back off. One thing to be aware of, mirage displaces the target in the direction of the wind. What you are looking at then is a phantom, and the image you see is a few inches or more, depending on the distance, from the real target in the direction of the wind. A 190-grain bullet with a ballistic coefficient of between .5 and .6 and driven at 3,200 fps will take about 2.6 seconds to reach 1,500 yards and over 3 to reach 1,760 yards (1 mile).

By practicing at your new location you have solved the problems of bullet flight such as spin drift, lift, your new comeups requirements, and your limitations. Though brief, this article may help set you on the path to making productive hits at mid, long, and ultra long range if that is your desire. The farther you shoot, the more work you must put in.

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barnes bullets, inc

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black hills ammunition

P.O. box 3090 RAPID ciTY, SD 57703-9574 (605) 348-5150, www.BLAcK-HILLS.cOM

BARRETT FIREARMS P.O. BOx 1077 MuRFREESBORO, TN 37133

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HORNADY MFG. cO. P.O. BOx 1848 grand island, ne 68803 (800) 338-3220, www.hornady.com

larue tactical

850 county ROAD 177 LEANDER, Tx 78641 (512) 259-1585

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nightforce 1040 HAzEN lane, OROFINO, id 83544 (208) 476-9814

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mike's gun sales & service jet supressors

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surgeon rifles, inc.

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perry-systems. iNc.

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rifles only jacob bynum 188 south F.M. 772, kingsville, Tx 78363 (361) 595-5472, www.RIFLEsONLY.cOM

sierra bullets 1400 west HENRY street, sEDALIA, MO 65301 (816) 827-6300, www.sierrabullets.com

superior shooting systems

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usA LAPuA & viHTAvuORI kaltron pettibone inc. 1241 ELLis street, BENsENviLLE, IL 60106 (630) 350-1116, www.viHTAvuORI-LAPuA.cOM

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