Finding the scope height is important in so many ways. If you’re into precision shooting, then how to measure scope height is a question you’ve faced many times.
A poorly mounted riflescope can affect the ease of use and comfort of a gun. It can also kneecap the gun’s accuracy. To maximize your gun’s potential, you need to measure the scope height accurately.
You need the scope height to measure DOPE (DOPE stands for Data On Previous Engagements).
In this post, I’ll show you how to measure scope height and its importance.
Why is scope height important?
Before we get started, let’s get a clear meaning of scope height.
Scope height refers to the vertical distance between the centerline of a rifle’s bore and the centerline of a scope’s objective lens.
This measurement is important for properly mounting a rifle scope because it affects how the shooter perceives the target and how the bullet trajectory aligns with the scope’s reticle.
A scope that is mounted too high above the bore will require the shooter to lift their head off the stock to look through the scope, leading to inconsistency in shooting form and potentially inaccurate shots.
Conversely, a scope mounted too low may cause the shooter to scrunch down and assume an awkward position to see through the scope, again leading to inconsistency and missed shots.
Therefore, it’s essential to choose a scope height that is suitable for your rifle and shooting style, to maximize accuracy and consistency.
Measuring scope height – Step-by-Step guide
There are two major ways of measuring the scope height. First, we have the easiest method, which is also considered slightly less accurate. Secondly, we have the cleaning rod method or the best method. It’s a more accurate method but one that is slightly difficult to use.
Let’s dive deep and see the two methods.
The Easiest Method (Slightly Less Accurate)
The easiest way to measure the scope height is to measure the objective lens diameter. With the diameter measurement (usually in millimeters), add around 2-4 mm before dividing by two. The 2-4 mm depends on the thickness of the scope’s body.
This is the simplest and fastest way to measure the scope height. But you can make the measurement more accurate by measuring the scope’s body diameter. It is much easier than a 2-4 mm estimation. Then go ahead and divide by two as usual.
If you get the scope diameter in inches, go ahead and convert it to millimeters. This is done by multiplying the measurement by 25.4.
With the few steps above, you can easily achieve an accurate scope height measurement in minutes. This is a good way to ensure precise shots.
Cleaning The Rod Method – The Best Method
The cleaning rod method is regarded as the best way. It’s more reliable and offers superior accuracy. This method works on the same principle as the easiest method.
However, under the cleaning rod method, you must take off the bolt of the firearm. A cleaning rod is then used to locate the barrel centerline, hence the name.
The cleaning rod method is used when mounting a new scope or making adjustments to an existing setup. Here’s how to use this method:
- Remove the bolt from your rifle and clear the chamber to ensure that the gun is unloaded.
- Place your rifle in a gun vise or similar fixture to hold it securely in place.
- Insert a cleaning rod into the muzzle end of the barrel until it contacts the bolt face or breech.
- Make sure the cleaning rod is straight and level, and then measure the distance from the center of the rod to the flat surface where the scope will be mounted.
- This measurement will give you the height from the center of the bore to the mounting surface. To determine the height from the center of the bore to the center of the scope’s objective lens, subtract half of the objective lens diameter from your measurement.
It’s worth noting that the cleaning rod method can be less accurate than other methods, as it relies on the assumption that the bore is perfectly aligned with the rifle’s receiver. However, it can still be a useful way to get a rough idea of the scope height before making adjustments.
Once you have determined the scope height using any of these methods, you can use this information to choose the appropriate height of scope rings or mounts for your rifle and scope combination. It’s important to choose rings or mounts that provide the correct height and eye relief for your shooting style and preferences.
Measuring scope height formula
The formula for measuring the scope height is a simple mathematical equation. It can be used to calculate the distance from the center of the objective lens to the rifle’s bore centerline.
This formula is useful for determining the proper height of scope rings or mounts needed to achieve the desired height and eye relief for your rifle and scope combination.
It’s another reliable method that is often used by professionals.
Here’s the formula:
Scope height = (bell diameter / 2) + distance from the base to the centerline of the bore.
To use this formula, you’ll need to measure the following:
- Bell diameter: This is the diameter of the objective lens at its widest point.
- Distance from the base to the centerline of the bore: This is the distance from the base of the scope mount to the centerline of the bore. This can be measured using any of the methods we discussed earlier, such as a height gauge, ruler, or cleaning rod.
Once you have these two measurements, you can plug them into the formula to calculate the scope height. The result will be the height from the center of the objective lens to the centerline of the bore.
It’s important to note that this formula assumes that the scope mount is perfectly level and that the scope is mounted correctly. If the scope mount is not level or the scope is mounted incorrectly, the measurement may be off.
It’s always a good idea to double-check your measurements and seek advice from a professional gunsmith or shooting expert if unsure about any aspect of the process.
Determining the best scope height
Determining the best scope height for your rifle depends on several factors. There is no one-size-fits-all scope height.
Here are some general guidelines to consider when selecting the best scope height:
- Eye relief: The first consideration when selecting a scope height is eye relief. Eye relief is the distance between the ocular lens of the scope and your eye when the rifle is in the shooting position. The proper scope height will allow you to achieve the desired eye relief without having to strain or contort your head and neck.
- Shooting style: The shooting style you prefer can also influence the best scope height for your rifle. For example, if you prefer to shoot from a prone position, you may want a higher scope height to allow for greater clearance of the rifle stock. If you prefer to shoot from a standing position, a lower scope height may be more appropriate.
- Rifle and scope combination: The type of rifle and scope you have can also play a role in determining the best scope height. Different types of rifles and scopes may require different heights of scope rings or mounts to achieve the desired eye relief and clearance.
- Personal preference: Ultimately, the best scope height is the one that feels most comfortable and natural to you. It’s a good idea to experiment with different heights and shooting positions to find what works best for you.
Overall, selecting the proper scope height is crucial for achieving accurate and comfortable shooting. You require a proper rifle and scope combination. There are several methods to measure scope height. The few we’ve discussed above include using a height gauge, ruler, cleaning rod, or using a mathematical formula.
The best scope height depends on factors such as eye relief, shooting style, rifle and scope combination, and personal preference. Consider the factors and experiment with different heights to find what works best for you.
Lastly, seeking advice from a professional gunsmith or shooting expert can also help select the appropriate scope height for your rifle.
Travis Mike is a firearm enthusiast and author passionate about all things guns. With 10 years of experience in the industry, Travis Mike has gained a wealth of knowledge on the subject. He is skilled in gunsmithing and tactical training. In addition to professional experience, Travis Mike is an avid hunter and shooter, regularly participating in local shooting ranges and hunting trips.