We’re going to tell you all about parallax, how it’s going to mess up your shooting, and what you need to do about it. Before we get to that let’s talk about the ocular focus. That’s the first part of the setup on your scope.
The ocular focus is a ring on the ocular end here, and you notice that it will move. And you need to adjust that until the reticle is completely clear to your eye.
The way to do that is to look into a blank area. I like to look up into the sky, so that way my brain is not focusing on a target. My eye is focusing on the reticle, because there’s nothing else in the scope. While you’re looking up in the sky adjust until the reticle comes into crystal clear focus. That’s the first step in the setup on your scope.
Now let's talk about parallax and how we’re going to eliminate it in the scope. Most of your sophisticated scopes have parallax correction adjustments on them. They’re either on the turret, or might be on the objective end. In either case it does the same thing.
A lot of people think that these adjustments are about focusing the target clearly, well that’s actually the bi-product of what you’re doing. What you’re really doing is correcting parallax error. Now what is parallax error? Parallax is the result of having the target and the reticle not in the same plane. They’re separated by space in the image processing of the scope.
What does that do for you? Let's take a look and see what error that actually causes for you when you’re shooting.
Your eyeball would see this. If your eyeball moved around relative to the scope you would notice that the reticle, the point of aim, the center of the reticle, would move relative to the target.
Let's say it moves as much as two inches. Well you’ve introduced a two-inch error, in addition to whatever the dispersion of the rifle is.
If you got a half-minute rifle, now all of the sudden you have a two and half minute rifle. Now let's fix this problem and eliminate parallax error from the system by collapsing the reticle into the same plane as the target.
Now guess what, no matter where your head is, or where your eye ball is, even if you have inconsistent positioning on the stock, you have eliminated that error and the rifle will shoot to its exact point of aim.
Let’s head out to the range and see how this is put into practice. Let me show you just how easy it is to set the parallax on your rifle.
Some scopes have it on the objective. Some scopes have it on the turret. In any case don’t trust the numbers. Actually set it.
We’re going to adjust all the way to infinity to start with. I’ve got a target out there at 100 yards that I’m going to be shooting at. I’m going to take a sight picture on that target, and I’m going to start adjusting back until the target just starts to clear up. Get it pretty close.
Now I’m going to grab my rear bag and get off the gun, and move my eyeball around. You know I’ve still got about four inches of parallax out there. I’m going to continue to adjust. Move around a little bit. Keep going. Keep tweaking it until, there it is.
Now when I move my eyeball the crosshairs are no longer moving on the target whatsoever. So I know the rifle will shoot to its point of aim.
All right, when is this extremely important? It’s when you’re shooting groups on paper, load development, zeroing, or just want to know what the accuracy potential of the entire system is. That’s when you really need to get parallax cranked down to perfection.