The Rifle Data Book
To track the performance of your rifle and ammunition, and to discover tiny variances between "book data" and your own combo of rifle-scope-ammo, a precision rifleman uses a Rifle Data Book -- which we are simplifying by giving you a free page that you can duplicate and bind into your own book (see below).
Every time you shoot -- whether zeroing or practice firing -- log in each shot, continually updating and reassessing your performance with that rifle. Indeed, you should have a separate Data Book for each rifle you own.
How many rounds have gone through your barrel? Check the Data Book. How is your bullet's trajectory affected when the temperature drops 40 degrees? Check the Data Book. Is this lot of ammunition firing the same as the previous lot? Check the Data Book. Cumulatively, this book becomes a history of your rifle, and a diagnostic tool to analyze your shooting performance, enabling you to trace your growth and find fundamental problems that may require training emphasis.
Instructions for Logging Data
The Data Book page is designed to log ten shots -- the maximum you should fire into a single target. Ideally, a precision shooter plans each shot so it's focused, analyzed and carefully recorded. Not only does this help you develop patience and attentiveness to each shot, but it's a firing rate that prevents your barrel from heating, which could shift your bullet's impact point.
BEFORE YOU BEGIN FIRING: Enter the DATE, LOCATION, RIFLE SERIAL NUMBER, TYPE AMMO and its LOT NUMBER. For TODAY'S TRAINING EMPHASIS, enter one marksmanship aspect for your shooting session, such as "breathing" or "sight picture" or "follow-through."
TEMP (Temperature) is important because you may see changes in trajectory between hot and cold days. PRECIP means Precipitation -- is it raining, snowing, misty or foggy? By DRILL, we mean a Shooting Drill, such as running 100 yards before firing. WIND requires you to draw an arrow for the wind direction and a numeral for its speed, both of which may change after you start firing. BDC ELEVATION is where you enter your elevation setting, whether using a Bullet Drop Compensator or Target Knob, with room for both the initial setting and, as you begin shooting, a corrected setting. WINDAGE, too, has spaces for both an initial and a corrected setting.
And WHEN YOU START FIRING there's a miniature bull's eye to record SPOTTERS (Spotting Rounds) if choose to fire them. Save the other spaces, below, for the rounds you fire in practice. MY POS refers to your body position, such as Bench, Prone, Sitting and Offhand, which you may switch from shot-to-shot. CALL means Calling Your Shot, which you place on the tiny target, and then use a spotting scope to see where you actually hit. (The actual hit is plotted on the large target on the right -- see below)
TIME -- is entered if this was a timed shot or timed target exposure. Did you make it?
EST/ACT -- Refers to Estimated and Actual Range. When firing on an Unknown Distance Range, first enter your Range Estimate, then the Actual Distance. On a Known Distance Range, just enter the Distance.
After each shot, eye your target through a spotting scope and then plot the bullet's impact point on the LARGE TARGET, (right), using arrows and numerals. Each cross-hatch on this target represents 9 inches up/down or right/left, but you can use the unit of measurement that best suits your practice or distance -- just do it consistently. Remember, only ten shots per target, and per Data Book page
AFTER YOU FINISH: Jot down the TOTAL RDS (Rounds) FIRED TODAY, and the TOTAL RDS (Rounds) THIS BARREL, which is determined by adding the rounds fired today to the TOTAL RDS THIS BARREL from your last practice session. This is how you'll be able to track any decline in accuracy as the barrel wears. (However, that's not usually an issue until you've fired 3,000 to 5,000 rounds.)
And finally, there's a space for REMARKS where you enter any conclusions or special conditions from this practice session. Note any zero shift, or perhaps that you used a different bipod, a new scope, etc. It's also a good place to decide how best to focus your next practice session.
Usually at the end of a shooting session, I also cut out my target bulls eyes, then measure and file the groups in a three-ring binder, with one section for each rifle. This binder, along with my individual Rifle Data Books, contains all the technical information I need for precision shooting -- and I'm sure you'll find this works well, too.