Today in Language Lessons we talk about finding that sweet spot in the box like we all want to do. Or something. Mad Duo
Language Lessons: Eye Box
Being able to see what you’re shooting at can be a lifesaver, or life ender–however you want to look at it. Variable power scopes have several benefits, but are often mounted incorrectly. This lends to not shooting to your full capabilities. One piece of the puzzle in mounting a scope is ensuring you have proper eye relief. The end result is maintaining the position of your eye within the eye box so you can see what you’re shooting at.
Term: Eye Box
Category: Shooting Terminology
Relates to: Eye Relief Threshold and Exit Pupil
Application(s) of Use: Any shooting where a scope is used
Definition: The position of your eye behind a scope which allows for lateral and axial movement, on each magnification setting of that specific scope, while still maintaining a full field of view. In short, it’s the sweet spot behind the scope where you won’t experience scope shadow no matter how high (or low) the magnification is.
Why it Matters: Understanding that eye box exists and how to acquire it can be the difference between always having a clear view through the scope versus the view sometimes being shadowed. When you don’t have a clear field of view, the point of impact of your round will most likely not hit where you aimed.
Into the Weeds: How do you attain this mysterious, rarely talked about, eye box?
With eye relief being the distance your eye needs to be from the scope to have a clear view, the larger the exit pupil the more forgiving the eye relief is. This amount of forgiveness is called threshold. It is the distance you can move closer and further from the scope, while on a given magnification setting, and still keep a clear field of view. Since we’re discussing variable power scopes, the distance where those threshold amounts overlap is the eye box.
The easiest way to guarantee a clear field of view, and being within the eye box, is by mounting the scope while on the highest power magnification. Since most scopes have less forgiving eye relief on higher magnification, when you dial down the magnification you will still have a clear field of view.
To attain your eye box, mount the scope by:
- Shoulder the rifle and look through the scope
- Position the scope as far away from your eye as possible while still retaining a full field of view
- Make sure the view is clear on the highest magnification setting
- Then slowly dial down to the lowest magnification setting
- If you have a clear field of view on every magnification, you have mounted the scope so that you will be in the eye box
Exit pupil and magnification have an inverse relationship. Meaning when you increase the magnification, less light passes through the scope to your eye. When the diameter of your pupil is smaller than the amount of light coming through the scope, you are able to move your eye left/right/up/down within the diameter of the exit pupil and still maintain a clear view through the scope. Exit pupil will be covered more in depth in a future article.
In Summary, the eye box is the sweet spot behind a scope where you will have a clear view no matter which magnification you’re on. Getting acquainted with and learning how to fully use your preferred scope will make it your force multiplier while out on the range.
Emergency: Activate firefly, deploy green (or brown) star cluster, get your wank sock out of your ruck and stand by ’til we come get you.
About the Author:
Start your caviling and contravening because yes, Candice Horner is AFM. That is, Another Fucking Marine (we swear that if we put two or more of them in a room it becomes all Oorah-Chesty-Puller-Port Hole-Hathcock-Ladderwell, but fortunately we have a Klingon translator). A prior federal LEO and current Registered Nurse, Candice brings special skills to the table our current minions don’t, such as the ability to properly ensconce an IV after a long night of drinking (some of our minions are CLS trained, but that usually equates to missing the stick fourteen times before giving up). Like any good Marine NCO, she can spit shine boots better than a seasoned fluffer can suck, roll sleeves tight enough to make a tourniquet envious, and yell loud enough to bring a grown man to tears. Candice is an enthusiastic hunter, outdoorsman (outdoorswoman?), writer (writress?), and accomplished competitive shooter.