What Size Scope Rings Do I Need for Varying Mounts?

“What size scope rings do I need?” It’s a question most shooters ask, and it’s definitely not one you want to get wrong. If you’re unsure of how to measure scope ring sizes or how to check the size, you’re in the right place. 

In this article, we’ll be talking about different scope ring sizes and how to pick one based on the scope and firearm you’re using.

Key Takeaways

• When choosing scope rings for your firearm, factor in the ring diameter, ring height, and how you mount your scope.
• Picking the correct scope ring size ensures your scope fits well on the firearm, giving you a clear view of your target. 

For more reading on scope rings see our guide to 30mm LPVO mounts.

So What Scope Rings Do You Need?

Choosing the right scope ring is important. You want something that’ll fit your rifle scope snugly without the risk of damaging it. 

To make your work easier, there are three things you need to factor in as you pick scope mounts. Let’s take a look at each one of them.

Scope Ring Diameter

As you look for the right size scope rings, start with the diameter. Fortunately, this step is pretty straightforward as long as you know the specs of the rifle scope you own. 

Just check the size measurements of the tube diameter and select rifle scope rings that match the size. The most popular tube diameters are 1 inch, 30mm, or 34mm.

1-inch is generally popular among LPVOs and budget scopes tailored for long-range shooting. If you have a 1-inch scope tube, you need a 1-inch scope ring.

The 30mm diameter is typically found in high-magnification scopes. As this size means a larger internal adjustment range, you usually see this size used for scopes meant for long-range shooting. A rifle scope of this size is also more durable than a 1-inch scope, which makes it quite ideal for tactical situations.

Lastly, we have the 34mm. Because of the thicker tube body, it has even more space for internal adjustments and has greater durability. It’s also ideal for tactical and hunting situations. Be sure to get 34mm rings for this scope. 

Scope Ring Height

Next, we narrow down our choice by looking at height. To pick the correct height, you need to figure out two things: objective clearance and bolt clearance.

Rifle scope rings should be tall enough to ensure the rifle scope’s objective lens doesn’t sit on the barrel. This is what we call objective clearance. 

Bolt clearance is another important consideration when picking the height of your scope rings. You want the ring to be tall enough so that when you turn the action’s bolt and make a complete load and unloading cycle, it won’t hit the lens. It can affect the accuracy of the firearm if it does.

Scope ring heights are available in three options, namely low, medium, and high. That said, these tags don’t give a shooter the exact measurement. 

To make sure you have the right measurements, you can ask a gun store employee or search the internet for an example that matches your rifle scope. You can also buy a scope set that comes with rings. This eliminates the hassle of measuring the rings.

Some shooters may assume they can just eliminate the objective lens issue by getting taller rings. But no, this can’t work because if you want to get the most out of your elevation adjustment, you have to mount your rifle scope as close to the receiver as possible.

Consider How You Will Mount Your Scope

The last thing to keep in mind when selecting scope rings is how you will mount the scope on your gun, which has to do with your shooting style. When mounting a gun, two of the most important things you factor in are cheek height and eye relief, and they vary among shooters.

Rifle scopes with short eye relief have to be mounted closer to the eye to ensure accuracy. That means the rifle scope rings also need to be positioned closer to your eye. 

Now, if your gun lacks an adjustable cheek weld, you have to mount the scope as close to the barrel as possible because this calls for the least amount of cheek weld adjusting. No matter your shooting style, your goal should be to ensure that your eye can see through the rifle scope in a straight line.

For similar reading, see our write-up on mounting an LPVO scope to get the right eye relief.

Frequently Asked Questions

How high of scope rings do I need for a 50mm objective?

The scope ring height you need for a 50mm objective lens scope is one that is 0.300 inches (7.62mm) high.

What size scope rings do I need for a 40mm scope?

The size of the scope rings you need for a 40mm scope is about 0.270 inches (6.85mm), which is the medium category.