Have you ever felt during target practice that there’s something just a little off? Your gun is cleaned and oiled properly, and the scope’s mounted and zeroed accurately, so what’s the deal? Maybe you should double check your scope ring height.
The correct height of your scope rings could be as important as the scope itself. If the height is off, it will also throw off your aim slightly, as you will have to adjust your natural hold and rest of the gun in order to see through the scope. Never fear. This step by step guide is here to show you how to measure your scope ring height to be sure you truly attain a perfect fit.
items needed for this tutorial
Ruler and/or Calipers – These will be used to take the actual measurements. This is the super simple way. There’s no reason to get overly technical about it! You just need to measure from point A to point B.
Rifle and Scope – This kind of goes without saying. Your gun and scope are both needed for the correct measurements for the scope ring size you need.
Related Read: Bushnell Banner 3-9×40 Scope Review
You! – There’s nothing wrong with having somebody mount your scope for you, but it doesn’t make sense to have somebody else try on new shoes for you and tell you they fit! You need to be able to aim your rifle and look through the scope to be sure it’s a good fit for you. The perfect height for somebody else may throw you off, and you don’t want your hunt to suffer for this mistake. I have made this mistake myself.
Not in every case, but for the most part the general rule for scope ring height is to have your scope mounted as low as you possibly can without the scope actually touching any part of the gun. There are a few reasons for this. The first is that it’s easier to sight along your barrel if the scope is down close to that level.
The second is that it’s more natural (and a stronger hold) to bring the gun up with your cheek alongside of it to look through the scope. You naturally want to sight down the barrel anyway, so if your scope mount is too high then the gun is held awkwardly and your aim will be off. Too low and your view may actually cross the barrel.
The third is that the higher your scope sits the more abuse it will suffer from recoil and other impacts. Your body will suffer more abuse too if you have to hold your rifle in an unstable position to be able to see through a scope that’s on too tall of a mount. If it’s mounted too low, then your rifle and scope take damage from each other, or else the scope can’t fit tightly enough in the rings because it physically touches the receiver.
Related Read: What is a Cantilever Mount?
Measuring Your Scope Ring Height
Step 1 – Measure
You are looking for the height of the ring from the contact point on the receiver to the center of the ring, or to the bottom of the ring cradle. Take your ruler and measure from the center of the bore, or top of the stock if it’s a bolt action rifle, to the center of the objective lens. Some people like to go to the center of the windage knob. That’s about it.
If you think this is not accurate enough, you can measure the diameter of the bore, then divide by two. Then measure the diameter of the objective lens, then dived by two. Once you have these numbers, you can measure the distance between the scope and receiver with the calipers and add this number to the other two numbers. Either way, the measurement should come out pretty close.
Step 2 – Double Check
The rings that you mount should be the lowest possible number without the scope touching the firearm in any way, and still comfortable with a great sight view when you look through it. So, after you mount your scope, you will want to double check this and make sure it’s a good height for you. If not, you should adjust the height and recheck.
Additional or Alternate Steps
The above is, in my opinion, the easiest way to measure scope ring height, but there are some other ways. Some ways involve set calculations, or there are also some websites that will calculate your height for you. All you have to do is plug in the rifle and scope details. This is a great resource when you’re at a gun store and do not have measurement tools, or are looking at different scope options.
Why is scope ring height important? – Scope ring height is important because you don’t want your scope to be mounted too high or too low. If it’s too low you could damage your rifle or scope, because they would literally be touching each other, get an improper, loose fit or mess up your target view when the scope captures they end of your barrel in the image.
If it’s too high you could damage the scope with recoil or other trauma, or injure yourself if you’re trying to hold the gun in an awkward position to see through the scope. Also, if your holding your gun lower so you can see, you’re going to be off target, as you will no longer be able to line up the barrel.
Are heights generic, in small, medium, large and extra large? – Yes, to some extent. Different manufacturers may have classified a small, medium or large with different mm heights or to fit different sized objectives, so you will want to double check your sizes.
Are scope rings brand specific? – No. You can use scope rings from different manufacturers, but you must double check the sizes, as they may not match up exactly. In other words, Bushnell scope rings are not Bushnell specific.
Hopefully this guide was able to answer your questions about how to measure scope ring height and why it is such an important factor. Now that you know this information, you can be better able to properly fit your scope to your rifle and have a much more rewarding and accurate shooting experience.
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