The rifle scope is maybe the most important component in a precision weapon system. It is the connection between you, and the target; it is your fire control system. Your success in long range shooting depend on the quality of the scope, on the quality of the scope’s mounts, and on how it’s installed on the rifle. In this article, we are going to examine the desired features of a long range shooting scope. We will also see how to find the optic that will best suite our needs , in the myriad of options available.
Before choosing the scope, you should have clear in mind the kind of shooting that you are willing to do. If you are going to compete in 1000yd competitions, you’ll need a complete different optic than the one you’ll need for long range hunting or military style uses. Every different activity requires a different optic. One job, one rifle scope. If you are going to do different activities, or you are simply yet not sure, you can always strike a balance, but keep in mind that you’ll never get the maximum benefits.
There are, anyway, some common features that the optics must have, regardless of the activity. They are:
Ability to maintain zero: the scope must retain the adjustment from one shooting session to another, even after long periods of storage, and after transportation. If we lost the zero, we lost the ability to correctly set the adjustment. This is especially important in long range hunting and military style matches, since you don’t have sighting shots like in standard long range matches. High-end scopes, especially those that are long time proved on the hunting fields and battlefields, are virtually all capable of maintaining zero, but there might always be a mechanical defect. Mid-priced and low-priced scopes’ ability to maintain zero is always uncertain. It is also not easy to determinate if a scope is able or not to hold the zero, because a zero shift may be determinate not only by the scope’s mechanism failure, but also by the scope’s mounts poor quality or their improper installation, or even by imperfections in the rifle/stock assembly.
Adjustments accuracy and reliability: The rifle scope is an extreme precision tool. Its adjustments regulation are in the order of fractions of minutes of angles (MOA), or fractions of thousandths of radiant (mil or mrad). To meet this degree of accuracy, the internal mechanism must be itself very accurate. Sometimes we can find (even in mid and high priced scopes), that the values of the regulations are not exactly true; a “click” of adjustment doesn’t exactly correspond to the declared value. At short ranges, we’ll never notice the difference, but going farther with the distance the error will multiply, becoming a reason for misses. In addition, sometimes the mechanism can “lose some clicks” meaning that it doesn’t get all the amount of correction we set on the turret. To check if your scope “loses some clicks”, once your scope is perfectly zeroed, you rotate the elevation turret all the way up and then all the way down a couple of time. then you set it back to your zero and shoot again. If your shot doesn’t go in the aimed point, it means that you have “lost some clicks” during the dialing process. If that happens with a high priced scope, generally you can have it changed, because that’s not acceptable. To test the true click value, you can follow this article I wrote about the topic.
Adequate amount of total elevation adjustment: Trajectory have a lot of drop at the farthest distances, and this means that we need a lot of elevation adjustment to be able to aim at farthest ranges. For example, to shoot at 1000y with a 308 we’ll need about 39 MOA, or 11 MIL, of adjustment from a 100y zero. The longer the distance, the more the needed elevation. When we select the scope, we must be sure that the total elevation adjustment meets our needing. Keep also in mind that when we zero our rifle, we usually “burn” half of the total excursion so, if a scope is declared of 80MOA of total adjustment, we’ll be able to utilize only about 40MOA. Consider also that it is not good practice to go work near the adjustments end. The total elevation adjustment of a scope is dictated by how the internal mechanism is engineered, and is declared by the manufacturers. Generally, scopes with a larger tube diameter have a greater total amount of adjustment. If the total adjustment of our scope is not enough, we can fix this problem mounting the scope on an inclined base, or with particular scope rings. But we’ll discuss of this in the related articles.
Parallax adjustment: When you need extreme accuracy, you want to avoid parallax error, so parallax adjustment is essential on a long range scope. The parallax adjustment can be on the objective, or on a side knob. If it is on the objective, it’s very hard to regulate it from the shooting position, so if you don’t shoot at a fix distance it’s better to have it on the side knob.
The other characteristics of the scope are personal or related to the type of shooting activity. In the next article I’ll try to give you a insight as to make you able to decide what will best suit your needs.