Competitive Shooting

Computer Data: How to Develop Your “DOPE” for a Long-Range Shot

LP Brezny kneeling next to three life size silhouette target that were shot from a mile away

Thanks to modern science, we have many different methods of generating information about bullet behavior over vast distances downrange. Not so many years ago, this would have been a tricky task lacking a slide rule and some hard-nosed math data in hand.

When you’re sending a bullet 400, 600, 1,000, or 2,000 yards, you better have some idea of exactly where it is going to land. With modern computers — both desktop and handheld — we can get those answers in very short order. This part of the long-range game has been condensed into a small, plastic, mounted screen that, with the correct input information, will send the correct answers at the speed of light right back to the device in the palm of your hand.

Dope card with data for a .308 Winchester rifle
DOPE card generated for .308 Winchester as applied to a long-range big game rifle scope.

Devices to Calculate DOPE

By example, Kestrel’s weather meter with its data processing chip separates fact from fiction and tells the shooter where to hold on a 1,000-yard target. Be advised, however, that this type of system takes wind measurements at the muzzle, not downrange. When shooting long, the weather can change across a mile of open canyon or even at 1,000 yards here in the American West.

In some cases, companies are working on — and have achieved success — designing almost fire and forget long-range rifle and cartridge systems. In effect, using a special scope and paired cartridge, you simply put the lighted dot on the target. When everything is correct and the trigger has been pulled, the rifle will fire automatically.

Now, we are talking about very high-tech systems that require a power source. These systems are far from being battlefield or tough, backcountry-use ready. However, the technology does exist. I have test-fired these systems successfully to 1,000 yards.

Currently, the folks at Trijicon are building a new binocular downrange wind measurement system that makes use of a Doppler LINDAR engine. In effect, the system can measure wind velocity at long ranges. This system uses a laser doppler to measure particulates in the air at the target.

Trijicon’s binoculars will measure six different ranges at the same time and are effective (according to Trijicon) out to 5,000 yards. It goes without saying, this will not be a backyard toy. The price is well into the next ZIP code — as is its effectiveness.

Two rifle set up for long-range shooting with dope card taped to the rifle stocks
DOPE card attached to field rifles during some long-range applications in the field.

Talking with the folks at Trijicon I have been informed that the product is in the final stages of testing, and I am on the list to get hold of one for a real-world downrange field review. If effective in the field, it will make a massive dent in the downrange information assessment filed today. We can currently factor bullet drop and drift to some degree, but we can now actually measure exact wind speeds at a target, and this is a major step in the right direction as applied to advancing computerized downrange measurement systems.

Generating your downrange firing solutions, or as we say DOPE (Data On Previous Engagements) — a term developed by military snipers for the most part or at least made popular of late — can be as easy as lighting up your desktop home computer. Many bullet and fixed ammunition companies offer shooters detailed database information. This information details exactly what a bullet will do in terms of drop and drift simply by painting in the correct information about the bullet, and then hitting the Calculate button on the keyboard.

With this information in hand, you can print and save it to data sheets. With the data sheets, you can then build compact DOPE cards to attach to your rifle. Afterward, you’ll be carrying a deadly, effective, known or applied database that details the performance of your selected rifle and cartridge. DOPE cards can be taped to the buttstock of a long-range rifle.

Dope card data for a .338 Lapua chambered rifle with data using Hornady's ballistic app
DOPE card on author’s rifle stock generated for the .338 Lapua at 1,000 yards.

I often use Hornady’s database. It gives information regarding the drop and drift of its bullets, or anything you put into the program and is displayed on your computer screen. Even a 300-grain Sierra MatchKing, as applied to the massive .338 Lapua, will drop out of the sky and onto the target’s face from about the distance of a two-story building at a mile. Only computer math can generate enough information to make this shot even remotely possible. In some cases, this information is currently being pushed to over three miles for a new world record long-range shot. Therefore, never say never, and the end seems to be nowhere in sight in terms of exact distances a rifle can be shot accurately.

 Recently, a Texas shooter broke into the three-mile world record distance shot with a shot from his ultra-long-range rifle and special breed of the .408 caliber CheyTac cartridge. While we are not talking here about shooting miles, rather building on a learning curve around closer range shots, be advised that like many of us who started slow, and closer in terms of range, you will get the bug to shoot farther and farther as you build on your equipment and learn more as you shoot from a ground matt or shooting bench.

What do you need?

Today, I use up to five different ballistic programs that are programmed directly into my iPhone or housed in my desktop office computer. With these ranging and computing systems and a weather station on my phone that also measures elevation and pressure systems on board, I have enough data to make a 2,000-yard shot, when required.

Talon Precision Optics TrackingPoint .338 Lapua LM OTM ammunition
This ammunition is developed for use in the almost fire and forget long-range sighting systems. Lacking this you’re going to have to do some light math or put raw information into computers for the answers.

What is required? Most of the data will be generated on your home computer or smartphone. Additionally, you will need to enter the type of bullet and grain weight as well as the bullet’s Ballistic Coefficient (BC) figures. Weather conditions, as in altitude, temperature, and barometric pressures will be addressed. You’ll need the exact range or ranges you’re going to be shooting, and the data point increments of 100-yard intervals or less.

The retained velocity of the bullet, for each range point indicated, will also be available to the shooter. This gives an indication to the shooter as to when and where the bullet’s transonic range will start to develop, and bullet performance fails. Information that is critical to target shooters and long-range hunters. Also included are the bullet energy at each measured range, time of flight (TOF) in seconds, bullet drop in inches, wind drift, and lead for wind in 10 mph increments.

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Many programs will display scope adjustments in MOA and MRAD increments. Using the data the program calculates, it is as simple as click and shoot, or at least that’s how it is supposed to work. An example I have often used in this area was the day I came upon a group of long-range shooters on the open Dakota Prairie testing some new scopes and rifles to 1,500 yards. I figured by just observing and making a couple of quick notes that they guys were using about $9,600 in equipment to measure everything downrange.

The rifles were ultra top-end and chambered the correct cartridges for the task at hand. However, the end results of their efforts were a great big goose egg at the end of the day. They could not hit that steel plate at about three-quarters of a mile. Why? The target was placed in high, wet grass. There was no bullet “splash” observed when the target was missed, and there was no way to adjust for impact save for “hunting” across the rifle scopes turret settings. That method was just not working out well at all for them.

Final Thoughts

The old story of one shot, one kill that you see on TV is just that in many cases — scripted, not reality. We all get lucky at times, ‘old school’ sight-and-observe shooting is still a good way to correct your zero quickly and hit that steel plate or whatever into the next ZIP code.

Kimber .308 Win./7.62x51 NATO sniper rifle resting on shooting bags resting on a shooting bench with Black Hills Ammunition Match cartridges
The author’s Kimber .308 Win./7.62×51 NATO sniper rifle. Solid rifle and scope still require good ballistic date to hit a target well downrange.

When I started all this long-range stuff, I was very pleased to hit a steel target at 500 yards and wrote about it extensively at the time. I am sure the big boys in long-range shooting thought I had lost my marbles — some four decades ago.

 Keep this little jingle in mind when you’re shooting, “If you don’t know the bullet drop, you’re bound to flop.”

Do you enjoy taking a poke at longer distances? What was your longest shot? How do you calculate your DOPE or do you just apply a little Kentucky windage? Share your answers and long-range shooting tips in the comment section.

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