Scopes are built differently and this is to fit the different categories of people using them. Manufacturers want every need to be catered for that is why they put so many features into a scope. One of such features is the turrets. They allow the user to adjust the scope to improve accuracy. At the forefront of this adjustment is MOA.
Without understanding what MOA is and how it affects the scope, you cannot adjust the turrets properly. So, first things first, what is MOA?
MOA is a minute of angle and this is a unit of angular measurement. This measurement is used to adjust the scope turrets. Typically, when people hear MOA being mentioned, they are lost on what it is or how it is calculated. This guide puts an end to all the confusion. But before we dive deeper into what this is all about, you should know why you should be interested in learning about MOA.
Most scope turrets are calibrated in MOA and without full knowledge of what it is and how to properly calculate it, you will not be able to make the necessary adjustments for increased accuracy.
Table of Contents
What Does MOA Mean On A Scope?
Remember, MOA stands for a minute of angle and is a measurement used for calibrating scope turrets. Another thing to take note of is MOA is an angular measurement, which means its figure is relative to distance. So every MOA is tied to a particular distance.
There are 60 minutes in one hour so taking minutes per angle into context, one minute per angle is 1/60. 1 MOA is also 1.047 inches at 100 yards, remember MOA is also tied to distance.
Because of the ambiguity and for ease of calculation, 1 MOA is approximated to 1 inch per 100 yards. You may be wondering why this is so and how it will affect the accuracy of your adjustments. Well, because of the distance (100 yards) this discrepancy (0.047 inches) is hardly noticeable. The approximated version also makes for easier and faster calculations.
MOA Turrets
As earlier mentioned, most scopes have MOA-based turrets and these turrets have specific MOA figures to guide your calculations. They can be anything from ½,1/4, 1/8, etc. Typically, the further it is from 1, the smaller it can measure.
See it this way, if 1 MOA at 100 yards is 1”, ¼ MOA at the same distance would be ¼”. The smaller the MOA, the better the accuracy. This is why long-range scopes are mostly fitted with 1,4” and sometimes 1,8” MOAs as they will allow the user to finely adjust the turret.
At 100 yards the neglected 0.047 inches will have very little effect but at 1000 yards it becomes a whole new issue as your shot will be skewed so hard, you may miss the target entirely. To combat this, scope manufacturers use a finer MOA for long-range scopes.
Know that 1 MOA is 1 inch at 100 yards, 1 MOA is 2 inches at 200 yards, 1 MOA is 5 inches at 500 yards, and so on. This means the same MOA will move different distances at varying lengths. Here is a simple formula I use to know the adjustment an MOA can make at a distance: the adjustment a single MOA can make is equal to the total distance divided by 100.
MOA is important if you want to zero your rifle to get absolute accuracy. Before you can say your rifle is zeroed in, your point of aim through your scope must be equal to your bullet’s point of impact.
Calculating MOA
Now to the main target, calculating MOA. How do you make meaning of your MOA and use it to make adjustments when zeroing?
The first thing you need to know is the MOA rating of your scope as this will be the basis of all your calculations. You can find this close to the turrets in most scopes.
While some people frown at the use of “clicks” to explain MOA adjustments as they claim it can be confusing since scopes come with different MOA s. I believe that you should embrace the use of clicks especially when you’re just starting. It is not only easier to understand, but it is also faster to implement and no, you’ll understand so well that it won’t get confusing even if you change to another scope with a different MOA rating.
Here’s what you need to understand about relating “clicks” to MOA adjustments: for a ½ MOA scope, every click moves ½” so to move 2” you have to produce 4 clicks in the direction you want to change (we’ll briefly talk about direction later). This is assuming everything is happening at 100 yards. Remember, at 200 yards, 1 MOA will make 2” adjustments and so on.
To make this section easier, we’ll be using real figures as examples.
For example you’re zeroing in your rifle with a scope with MOA of ½ and after taking your first group shot at 100 yards you notice they were off the bull’s eye by 2” to the top. What this means is that your bullet is 2” above its intended target and you need to adjust its elevation to bring it 2” downward.
To do this, here’s what you need to remember:
- At 100 yards 1 MOA moves 1”
Since our scope is ½ MOA per click, we’ll need to make 2 clicks to get 1” adjustments and 4 clicks to get 2” adjustments on the elevation turret and in the direction needed.
Another example: let’s say this time around our scope is rated ¼ MOA and we’re shooting at 100 yards. If we notice a 1” deviation from our intended target how do we remedy this?
We do this the same way as the last example, bearing in mind the following:
- 1 MOA moves 1” at 100 yards and 2” at 200 yards.
- This means ½ MOA will move 1” at 200 yards and since our scope is rated ¼ MOA, we only need to make two clicks to move 1”.
- After making these adjustments, you should come as close as possible to your intended target depending on the accuracy of your scope. Some scopes offer better accuracy than others. The principles are the same no matter the scope or distance.
MOA For Larger Adjustments
All the examples we’ve been showing were of smaller adjustments. 1 MOA, 2” and so forth, but what if we want to adjust 500 inches or 50 MOA at 1000 yards? (You know how this came about, right?: 1 MOA = 1” at 100 yards and 10” at 1000 yards).
To make such large adjustments where it is so cumbersome to count in clicks, we’ll make use of an easier method. On a ¼ scope, you’ll need to make 200 clicks to move 500 inches. But counting 200 clicks will bore you to death plus waste your time so a better way to do this is to count the revolutions. A typical scope will have a turret capacity of 20 MOA. Even if yours is not 20 MOA, you can still follow these steps to make the necessary adjustments.
Since one revolution is 20 MOA and we need to make 50 MOA, this means we need to make 2 and a half revolutions to complete 200 clicks on that scope and achieve our desired accuracy.
See how easy this is? You can use this understanding to adjust any distance you want on your scope.
Summary
The abbreviation “MOA” may seem abstract and confusing but it is as plain as possible once you get the basics right. The importance of knowing what MOA is and how to calculate it cannot be overemphasized. From helping you zero in your scope to reducing the time spent aiming, understanding the dynamics of a scope’s MOA is vital.
