What Do the Numbers on a Rifle Scope Mean?

by Joe Steel
Close-up of rifle scope.

Close-up of rifle scope.

Rifle scopes can accomplish more than one thing. For one, they relieve the shooter of the worry of lining up the front sight with the rear sight and of losing focus on the target while lining up the sights. Also, of course, rifle scopes magnify the image, making hitting the target all that easier. The numbers on the scope tell you the size of the lens and how much it magnifies.

Numbers

The first number on the rifle scope signifies its magnification power. For example, a 4 X 32 sight means the scope magnifies the image four times. A 6 X 32 sight would denote a scope with a six-power magnification. Some scopes have variable magnification, which you select by turning a power ring on the scope. A 4 - 12 X 32, for example, magnifies between four and 12 times. The second number on the scope indicates the size in millimeters of the objective lens -- the one closest to the end of the barrel. So, a 4 X 32 scope would have a 32 mm lens.

Considerations

When choosing a scope for your rifle, consider that as magnification increases, brightness diminishes. At 4X magnification, the image in the scope will be brighter with a 50 mm lens than with a 32 mm lens. Bigger lenses cost more, of course, and they also weigh more. Depending on the type of hunting you do, higher magnification or brightness may not be worth the extra cost. At lower magnifications levels, a 50 mm lens won't provide a lot of extra light compared to a 40 mm lens, for example.

About the Author

Joe Steel is a Northwest-based editor, writer and novelist, former news editor of an outdoor weekly. He also was an editor at a Seattle-based political weekly and editor of a monthly business magazine. He has been published in the "Seattle Times," the "Washington Post" and the "Foreign Service Journal," among other publications.

Photo Credits

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