Until the invention of hunting rifles, in the late Eighteenth Century, firearms did not need sights. Once accuracy had been achieved, though, sighting became paramount to success. And, when the only meat in the diet came from hunting, shooting well was part of staying alive.
As the range of modern rifles improved, in the Nineteenth Century, they became capable of hitting targets beyond the shooter’s sight. The idea of attaching a telescope to the rifle was a logical next step. Scope-equipped shooters could hunt at great distances. This increased the usefulness of the rifle in the dinner-gathering area, and improved the safety margin for hunters of dangerous game. It altered the meaning of the phrase “hunting widow” from its former, more deadly definition.
A scope gives a shooter several advantages. A clear view of the target makes better shot placement possible and makes it easier to identify the quarry. The lives of many hunters and cattle have been saved by rifle scopes. The magnification used is a function of the hunting environment. When hunting in brush or woods, the scope is an aid to the hunter’s eyesight. Nothing more than 4X is needed, and hunters in these conditions use iron sights if their eyesight permits. When hunting in open country, in terrain with longer sight lines, scopes up to 12X are appropriate. The field of view will be narrower with a higher powered scope, and the hunter may miss seeing some game. The typical hunter, with just one rifle, usually chooses a variable power scope. The most popular sold today is 3-9X; it gives the hunter the flexibility to hunt at all but the longest ranges.
When a hunter looks through a scope, he sees the scene before him projected on the retina of his eye. Scopes are designed with something called “eye relief” built in. Rather than placing the eye directly against the lens of the scope, it is positioned well behind it. This is a necessity in the design of rifle scopes, as the recoil of the rifle can slam the scope into the eye if space is not allowed. Most scopes allow an eye relief of around 3-1/2 inches, but they all vary. When the scope is being mounted the shooter can experiment to find the best position. Some scopes are designed with long eye relief for mounting forward of the ejection port. The other thing seen through the scope is the reticle.
The reticle is engraved on one of the optical elements internal to the scope. A properly aligned scope will place the sight on the impact point of the bullet at 100 yards. Scopes that are designed for very long distances will be aligned differently. The basic reticle is a crosshairs, but there are other types. A hunter who is investing in a quality scope should try different reticles to find the one that best suits him and the hunting that he does. Some reticles have additional marks on them allowing the hunter to determine the range and to compensate for crosswind or elevation. Range-finding marks on most hunting scopes are graduated to the shoulder height of a large deer. Parallax error is a slight change in point of aim beyond the range for which the scope is regulated. It is more noticeable in variable power scopes, but it can be ignored when hunting at ranges below 300 yards.
Quality is the most important factor when choosing a scope. All scopes available today, whether manufactured in Malaysia or Germany, have certain basic features. A scratch resistant coating on the lenses is important. This is what gives the objective lens of most scopes that funny color. Anti-reflective coatings should be on all of the internal optics, and the tubes should be sealed. High quality scopes have the tubes filled with an inert gas. The thing to keep in mind, after finding the right combination of power, eye relief, and adjustability, is that one gets what one pays for. If a cheap scope is mounted on a magnum caliber rifle it will not last long. Buy the best, it can always be moved to the next rifle.