storm data book

Data Books

In Blog by Rich2 Comments

Data books! I think that data books are pretty over hyped. This is not to say that they are not useful and don’t have their place. However, the average person getting into precision rifle shooting or tactical rifle competitions is probably under the impression that data books are more important than they are. So let’s discuss exactly what a data book is and whether or not you need to be using a data book as you get into precision rifle shooting.

What is a Data Book?

A data book is something that stems from Military Snipers and keeping records. The idea is that you have a data book which you record information about the shots you take in for later reference. The idea being that if you take a shot on a sunny day at 800 yards, you write down all kinds of information about how you made the shot. What was the temperature? How fast was the wind blowing and from what direction? This way if you encounter a similar situation in the future, you have DOPE (Data on Previous Engagements) to go off for that shot. The main idea is increasing consistency and maximizing your chances of a hit on the first shot.

storm data book

Storm Data Book

The data books are used to keep details of the rifle, and its performance, handy for reference. You can write down the number of shots you have through the current barrel and how many were fired on each day. Many data books these days have pre-printed pages of targets so that you can log where your hits were and analyze later how accurate the shot was. For example you may have thought you had a pretty spiffy wind call but when you examined the target you found the hits were all on the edge of the plate. You can then surmise that the sum effect of the wind was greater than you thought it was and therefore you need to add additional windage in similar conditions. You can even consult a drop chart, many data books include them for common cartridges, and see how much additional wind would have been necessary for a center or bulls eye hit.

Are Data Books Important?

Yes and no. The idea has lots of merit and potential but a lot of times the execution of the data book is somewhat misguided. Here’s what I mean. There is absolutely a lot of value in recording performance data for later analysis. That can turn a day of lousy shots into a really productive and educational experience if you learn from the mistakes. However, the notion that you should log every single shot and where the impact was on paper isn’t really realistic. For starters, if you are shooting in a competition or a MIL/LE type scenario, even out hunting, you don’t have the time.

You can’t take a shot at an animal as a hunter and then ask the other animals to hang out while you write down the information about your shot. If you are a MIL/LE guy the bad guys sure aren’t going to wait for you to jot down any notes you want to take. Even on a square range with no time factor or stress, do you really want to stop afterĀ EVERY shot to go look at the target and plot its impact on paper? It would take all afternoon to fire ten rounds with all the trips back and forth between the target and firing line.

The notion that a MIL/LE Sniper would have to consult a log bog or would always have the time to do so before taking a shot is ridiculous. Same with our Hunting readers. How many times have you almost stumbled upon the animal you were hunting? Do you have time to break out a notebook and check to see what adjustments you need for the shot? This is what I mean about the concept being executed poorly. The lore and legend that surround the data book are a little silly and a lot impractical.

Data Books Done Right

I said data books are useful, and I mean that. They absolutely are. You just have to use them properly. Rather than logging each and every shot, work on some aspect of marksmanship and take notes here and there. Don’t stop and break your shooting position up after each shot. Take a few shots, then if time and opportunity allow, jot down some notes on the shots. Were your wind calls good? Did they match up with your DOPE charts or did you have to add elevation or windage to your firing solution?

Try to get in a habit of writing down useful information that helps frame the lessons you learned for that shooting session, rather than arduously recording the details of every single shot. I always try to write down some notes on the wind. Specifically, what were the wind speeds averaging, and what were my holds to make hits at different distances. Then I can go back later and check the accuracy of my DOPE charts. If my DOPE charts are consistently calling for more or less elevation or windage than I need, something’s wrong. That’s the value of a data book. The ability to diagnose and correct errors.

impact data books shooters diary page

I like the shooters diary pages because they focus on taking notes of the lessons learned, less focus on logging every single shot

The photo above is from my Impact Data Books data book. These are their ‘Shooters Diary’ pages and are very well suited to jotting down the kind of information we are talking about. There are fields for jotting down the conditions and the windage/elevation used. Then there is a large area for notes. As you can see I write down a lot of information on what the wind was doing. I like to note the speeds, and I put different speeds on different lines along with the holds I used to hit the target at those ranges.

Data Books as a Reference Tool

I’m a fan of the Impact Data Book. I like that they offer ready to go books with standard sets of target and reference pages. I also like that you can order different sets of pages and customize your book or order refills for things you have run out of. Storm Tactical Data Books are also very well made. I use those as well. One thing I like that I see from Impact Data Books regularly is the addition of new sets of pages. When using a data book as a reference tool it’s nice to have relevant information at your fingertips. Both brands offer numerous free downloadable targets and log pages to go along with them!

data book reference pages

Both Storm Data Books and Impact Data Books offer many reference pages full of useful shooting information

For MIL/LE Snipers that might actually be doing the long range thing with bad guys running around, Impact Data Books makes a set of pages listing common object sizes and shapes. You might be verifying ranges or if your rangefinder goes down, you might be milling targets. It’s nice to have the size of a stop sign on hand, or an average door height, or window size, to use for reference. Most data books also come with drop charts for common cartridges and wind clocks for reference. I know I said the notion of using that stuff was unrealistic. I still think that trying to consult a data book in a real world hostile scenario is unrealistic. However, when time and opportunity are available, it doesn’t hurt to have extra information easy to access.

Other Data Book Goodies

When you buy yourself a data book, you want to keep it safe. You can even buy pages printed on write in the rain paper if you feel that’s necessary. I’ve not really found it to be but I’m not crawling around the Sand Box on active duty either. One thing you are going to want is a cover for your data book. Get something that will hold the book, along with some other goodies. I like to pack a mechanical pencil and eraser for jotting down notes and making corrections. I also like to take a sharpie along in my book for marking targets if I need to.

A lot of guys will add some analog tools for ranging and making angle fire shots to the pockets of their data books. Things like a Mil Dot Master and Slope Doper. They don’t take up a lot of room and it’s not a bad idea to have an analog backup to your digital tools like your rangefinder. The only downside to these are they are based on common cartridges and muzzle velocities. If you are running a hot rod caliber that isn’t common, the output from these tools is not going to work across different calibers and cartridges the products weren’t designed around.

data books - analog tools

Always good to have backup tools for your digital stuff, Mildot Master, Field Density Altitude Compensator, Slope Doper


Wrapping up the Data Book Topic

In summary, this is a great tool so long as you use it properly. Spend your time shooting, jot down some notes, and go over your data book later. If you are spending more time taking notes than you are shooting then you need to redirect your efforts. You aren’t learning a note taking class, you are out to shoot and get better at it. I’m not saying bang away at a target without taking time to reflect on the results and lessons you can learn along the way. Just don’t turn a range trip into a note taking trip. Fire a few rounds at a time and stop to take stock of the results and any changes you had to make on the fly for a hit. Write that stuff down!

Owner and Proprietor of AccuracyTech, LLC. Rich is a Firearms Enthusiast, Precision Rifle Competitor, and Writer. He is committed to bringing readers quality reviews and articles related to the Precision Shooting Sports. If you have any questions for him, please use the contact form on the site.


  1. This is my first time on your site and it is excellent. One question: I am interested in purchasing your data book plus the arm band with the attachable cards. Yet, there seems that you do not sell the products and other than a data book I do not know where to purchase the arm band or other items on the website. Please help.

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