Making the Long Shot

The Armed Canadian teaches you how to adjust for the long shot.

We won’t discuss 100 or 200 yards here. As I said, my rifle is zeroed at 200 yards. Where I put the crosshairs is where the bullet will theoretically land at that distance. 300 yards is where it starts to get interesting.

Consulting the ballistics table for the 139gr boat tail round I am shooting (yes, they break it down by weight and bullet type, each fly differently), I read a drop of 8.4 inches at 300 yards. Great! Assuming no wind and a perfect shooting, my rounds will be clumping 8.4 inches below the bullseye if that is where I am aiming. If I want to put the crosshairs on the bullseye and hit it, I need to adjust the scope so it raises the point of impact to meet the point of aim. In other words, I need to raise it by 8.4 inches.

That’s where the calculator comes into play.

8.4 inches is not a value in MOA. We need to translate it into MOA. We do this by a very simple formula:

deviation in inches / (range in yards / 100)

This works for the known ranges where you have drop figures for. For those that you don’t, you need to guess. What this formula does is translate your drop in inches into drop in MOA. Once you have that, you can adjust your scope. So if we plug in 8.4 inches and 300 yards, we get a value of 2.8 MOA.

Since my scope is adjusted in 1/4 MOA increments, we multiply that number by 4 (or divide by 1/4 or .25). That gives a value of 11.2. This is the number of clicks in “Up” direction I need to dial into the elevation turret on the scope to bring the rounds onto the bullseye.

You do the same thing to account for wind. If the wind is blowing your rounds 2 1/4 inches to the right at 300 yards, you have a deviation of 0.75 MOA. For a 1/4” MOA scope, this means you dial in 3 clicks of “Left” adjustment to compensate.

Hat tip Firearms & Freedom.