RIFLESCOPE TECH-TALK

COATED OPTICS

Lens surface coatings reduce light loss and glare due to reflection for a brighter, higher-contrast image with less eyestrain.

Coated - A single layer on at least one lens surface.

Fully Coated - A single layer on all air-to-glass surfaces.

Multi-Coated - Multiple layers on at least one lens surface.

Fully Multi-Coated - Multiple layers on all air-to-glass surfaces.

MAGNIFICATION (POWER)

Riflescopes are often referred to by two numbers separated by an "x". For example: 4x40. The first number is the power or magnification of the scope. With a "4x", the object being viewed appears to be four times closer than when seen with the unaided eye.

OBJECTIVE LENS SIZE

The second number in the formula (4x40) is the diameter of the objective or front lens. The larger the objective lens, the more light that enters the scope, and the brighter the image.

PARALLAX

Parallax is a condition that occurs when the image of the target is not focused precisely on the reticle plane. Parallax is visible as an apparent movement between the reticle and the target when the shooter moves his head or, in extreme cases, as an out-of-focus image.

An easy way to visualize parallax is to hold a finger from each hand pointed at each other – one pointing up, one down (as pictured in figure 1). Let’s pretend the top hand represents the target, the bottom hand your riflescopes graticule / cross-hair. Move your head from side to side – and of course the fingers stay aligned. Now, move the top hand further away from you (as in figure 2). Move your head from side to side again (without moving your fingers), and just like a scope with parallax not set to the distance of your target, you’ll see a shift in relation of one hand to the other:

Bushnell center-fire riflescopes under 11x are factory-set parallax-free at 100 yards (so must be sighted in at 100 yards); rim-fire and shotgun scopes at 50 yards (so of course should be shot in at 50 yards). Scopes of 11x or more have a special range focus to adjust for parallax.

SEALED, WATERPROOF, AND FOGPROOF

Bushnell riflescopes remain crystal-clear in all types of weather. All 1" and 30 mm diameter riflescopes are not only nitrogen- or argon-purged to remove any vestige of internal moisture, but they are also O-ring sealed to prevent the entry of dust or moisture.

How To Choose

A quality riflescope is the key to a successful day at the range or in the field. Riflescopes bring distant targets and surrounding objects up close and personal allowing safer, more accurate shooting. They gather and utilize available light making it possible to shoot in lower light conditions and allowing the hunter to hunt from dawn to dusk.

Pairing just the right riflescope with your gun and ammunition will help you get the most out of each and every shot. Selecting the correct scope to fit your needs involves a number of considerations from mechanics and construction, to image quality and magnification. Keep in mind when and where you shoot most often and choose a riflescope with features that best fit the requirements of your particular sport.

Mechanics

The inner workings of a scope have a direct affect on shooting accuracy. As adjustments are made during sight-in, the cam tube, which holds the reticle and lenses in place, moves inside the scope. To stay on target and produce a quality image, this tube must be strong enough to absorb the impact of heavy recoil during shooting and remain in place. When selecting your riflescope look for precision (positive) adjustments, point-of-impact consistency, reticle strength and waterproof, fogproof and shockproof durability. You'll also want to consider weight, bulk and ergonomics, which are especially important during long days in the field.

Image Quality

For optimum image quality, it is important that the optical system of a riflescope deliver as much light as possible to the eye of the shooter. The lighter or brighter the image, the sharper the resolution, and the clearer the shot. The quality of the glass, lens design and optical coatings all contribute to a riflescope's ability to manage light effectively. When selecting your scope, consider magnification, objective lens size, exit pupil, resolution, field of view and eye relief.

Magnification

Choose a riflescope with the magnification or power that is appropriate for your particular application.

Low power - (example: 1.5-6x32, 2-7x32) These riflescopes are ideal at close range and for shooting moving targets. They provide the most effective light management and produce a brighter sight picture and wider field of view-even in low-light conditions and thick brush.

Medium power - (example: 3-9x40, 2.5-10x50) Select these riflescopes for hunting big game at medium range.

High power - (example: 6-18x40, 6-24x40) These riflescopes are best for target shooting, when the target is motionless and for varmints and other small game.