On our scopes, we have an elevation turret (up & down) and a windage turret (left & right) Although, typically you hold for wind (but more on that in a minute). If you look up charts, graphs, or a compass for wind, you will see there is zero windage correction for 12 and 6 o'clock. Technically, that is true. There is no windage adjustment, but we will adjust for wind from 12 and 6 o'clock. Let me clarify. A 12 and 6 o'clock correction will be made, just not on our windage turret. It will be made on our elevation turret. Think of it this way: when you're running with the wind to your back, you can feel the boost it gives you. But, as soon as you change direction and run into the wind, it's a bit of a struggle. Well, this is the exact same thing that happens with a bullet. A 12 o'clock wind will have more drag on the bullet, slowing it down and causing it to be exposed to gravity longer. The opposite is true with a 6 o'clock wind . The bullet has less drag and is being exposed to gravity for a shorter amount of time. That means the wind will have an effect on the bullet, causing it to hit high or low. The good news is, this is easy to calculate and correct for. Formula: Wind Velocity (MPH) x Distance (Hundreds of Yards) /4 (Constant) = Yards (Range Change) 10 (MPH) x 5 ÷ 4 = 12.5 Yards One method (which is not the one I prefer) is to add 12.5 yards for a 12 o'clock wind, or subtract 12.5 yards for a 6 o'clock wind. This is done with a ballistic calculator. But, if you have a ballistic calculator, it should be calculating this for you, and thus you don't need the formula. While this is the easiest method, batteries die, or electronics get too cold, too hot, or they get wet, and can quit working. So, I'll walk you through how I calculate and dial for this. First, you will need a ballistic calculator. I like JBM Ballistics (Online) or Strelok Pro. (Phone App) Set all of your inputs to your zeroed conditions. This is the environmental conditions that your rifle was zeroed in. Make sure the wind inputs are zero. This should produce a drop table; copy and paste this or write it down. Next, set your wind to 10 MPH @ 12 o'clock (or 0°). This will produce a drop table that is now calculated for a 12 o'clock wind. Now, subtract the lower number from the higher number, per 100 increments, and that is your correction value. Then, set your wind direction to 6 o'clock (or 180°), and the difference between this table and your zero wind will be the correction value for a 6 o'clock wind. Example: Zero wind 200 - .4 300 - 1.1 400 - 1.9 500 - 2.8 600 - 3.8 10 MPH wind @ 12 o'clock 200 - .4 300 - 1.1 400 - 1.9 500 - 2.9 600 - 3.9 Wind correction value Dial up 200 - 0 300 - 0 400 - 0 500 - .1 600 - .1 Just repeat this same process for a 6 o'clock wind corrections value. These are your tables for your dope. I personally print these out and have a set of drop tables that I keep in a small binder (Firing Solutions Book) with the firearm. These can be used as the main tables for your firing solution, or as a back up to your electronic ballistic calculator. Either way, you should always have a printed copy of your tables. I will usually use my ballistic calculator for my dope and confirm it with my tables. This does two things. First, it will confirm that there are no mistakes in your inputs on your ballistic calculator. Second, it keeps you using your tables, so if you ever have to rely solely on them, it is still very quick to gather your firing solution. I usually have a dope chart taped to my rifle that includes: Drop table, 10 mph wind (90°), 10 mph wind (0° & 180°) and spin drift. This allows me to make an accurate shot, very quickly, with no equipment. So, next you're at the range, try out your new table for 12 and 6 o'clock wind, and see how it works for you. The Overwatch
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