How To Lap Rifle Scope Rings

Shooting is an amazing sport that people around the world use for a number of reasons. Some shoot to relax, others enjoy competition, some practice for self-defense, some hunt to survive, and there are still more reasons that you might want to engage in the sport of shooting. A fair amount of people who have never shot before think that it is all about putting bullets in the gun and having at it. But in reality shooting is a sport and it requires you treat the equipment just like you would any other sporting equipment.

Attaching a scope to a rifle is shown in movies and video games as being as simple as slapping it on and going. In reality, there are a number of steps that you need to take in order to mount a scope. Some of those steps are required, others are optional and recommended, others are just optional.

Lapping is a process in which you modify the rings that are used to mount a scope. Scope rings come from the manufacturer with a machined surface on the inside. Because scope rings are often times usable on a variety of scopes, they come with a fairly generic machining. This machine is not perfect and is likely not designed to fit your specific scope. Even if the scope rings are made for your scope, they are often not perfect still.

The process of lapping scope rings is designed to help with this. Using tools you true up the inside of the scope rings. In this article we are going to talk about how to lap scope rings so that you will be prepared to make your scope as accurate as possible.

What is Lapping Scope Rings and How To Lap Scope Rings

Image by Adamrpatel97 | CC BY-SA 4.0

Why Would You Lap Scope Rings?

We already mentioned that most scope rings don’t come perfect surfaces. The lack of a perfect surface can result in a number of issues, including: damage to the outside of the scope tube, reduced stress on the tube, additional accuracy from perfect mounting, reducing chances of the scope moving in the rings, and more. These factors are all important to the proper operation of your scope and rifle.

While premium and OEM scopes often need lapping, it is especially important if you have cheap scope rings. For first time shooters, you probably aren’t going to immediately invest in scope rings that are well over $100. You are going to get what is affordable and basic. That is fine, just know that they should be lapped.

How To Lap Your Scope Rings

Lapping a scope ring is a process that many people aren’t familiar with. One of the ways that you can lap a scope is to have it done by a professional. A gunsmith can lap your scope rings if you need it. Turning to a professional will help to ensure that the job is done perfectly. The downside is that they will charge you for the surface and depending on the workload of the gunsmith, it might take some time.

Alternatively you can lap a scope rings yourself if you want. The process isn’t too difficult, it just takes a bit of learning. We are going to give you step by step directions on how to lap your own scope rings.

What You Need

Step One: Mount The Scope Rings

The first step to lapping your scopes is to mount the scope rings. You will want to start by attaching the bottom rings. In most cases you can simply screw them on. Do your best to visually ensure that they are straight, leaving a little bit of looseness to adjust the rings for alignment.

From the lapping kit take the lapping tool and place it in the scope rings. Use the tool to ensure the rings hold it perfectly straight. Once the rings are straight, make sure not to move them while you tighten them down.

Step Two: Stabilize The Rifle and Apply Lapping Cream

Make sure that the rifle is in a stable location, preferably one that keeps it from moving. The easiest way to do this is with vise grips. Should you not have vise grips you can put it on sandbags and use your body to prevent it from moving. There are also specialized grips for working with rifles that you can use to prevent it from moving while you are working with the lapping bar or performing any other maintenance.

Remove the lapping bar and place the lapping cream that came with your kit onto the inside of both the lower part of the scope rings and the upper. You don’t want to apply too much cream, just enough to cover the inside surface of the rings.

Step Three: Insert The Lapping Bar

Now it is time to use the lapping bar for its intended purpose. Place it in the scope rings and put the upper part of both scope rings on. From there you will tighten the upper parts down. You want to tighten the scope rings down enough to make contact with the lapping bar but not to the point where you cannot move the lapping bar. This is where most people make a mistake, if the rings are too tight you can damage them instead of using the lapping bar effectively.

Step Four: Move The Lapping Bar

Push the lapping bar forward in the scope rings. Then, before it is all the way out, push it backward. Continue moving the lapping bar forward and back in the rings. This process will remove any burs or imperfections from the surface of the rings, because of this it will cause the lapping bar to become looser in the scope rings. That is okay.

It should take about one or two songs on the radio, or a few minutes, for the scope rings to become looser.

Step Five: Tighten The Rings And Continue

After the rings have become loose you will want to tighten them back down. Again, you want to tighten them enough that there is a firm grip on the lapping bar. Then you will repeat step four, moving the lapping bar forward and back.

Step Six: Inspect The Scope Rings

After you have used the lapping bar twice on the scope rings, remove the top rings and the lapping bar. Feel along the surface of the rings and determine whether they are sufficiently smooth or not. For high quality or well machined scope rings you will likely only need two or three sessions with the lapping bar. Lesser quality scopes will need more.

If your scope rings need more sessions repeat steps four and five until they are at the desired smoothness. Make sure to check the rings to ensure you do not overuse the lapping bar.

Step Seven: Mount The Scope

Once every ring is as smooth as you desire it is time to mount the scope. You will place the scope in the now smooth and straightened scope rings. Attach the upper rings and tighten them alternatingly to the manufacturers recommended tightness. Over tightening the rings will damage the scope. Before the scope is completely tightened down, take the opportunity to ensure that it is at the proper distance from your face and that the scope is properly leveled.

To level the scope use a set of levels on each of the adjustment knobs to ensure that they are completely flat. Rotate the scope gently until they are. And after you are done with that the scope is mounted and ready to be zeroed. Zeroing the scope is the process of adjusting the reticle in the sight to your eyes.

Now you know how to lap scope rings, you can use this to help ensure that your scope does not get damaged and is as accurate as possible. The process is relatively simple once you learn how to do it. The tools that are required all either come with your scope or are relatively inexpensive. Next make sure that you read our other articles on mounting and preparing a scope. All of our tutorials combined will help you to shoot like a professional.

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