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How to Lap Scope Rings and Why Lapping is Important?

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You want your scope to last long and perform well, right? Well, one of the best ways to ensure that is by lapping your scope rings but the question remains, how do you lap the scope rings the right way?

Well, it’s a question we have received over 25 times in the last month and this article, we’ll tell you everything you need to know in detail.

From a step-by-step guide on how to do it, what lapping scope rings mean and why any scope owner needs to do this if you are constantly looking to take your performance up a notch, you are in the right place.

So let’s get into it.

How to Lap Scope Rings and Why Lapping is Important?

Lap Scope Rings

Tools Needed To Lap Scope Rings

  • Scope Ring Lapping Kit
  • Allen key (should be provided by the scope manufacturer)
  • Polishing compound
  • Paper towels
  • Marker pen to label the ring sections
  • Screwdrivers

Step 1: Find the height

Don’t worry, you don’t need to get your measurement tapes out and start doing complicated maths, finding the height of your rifle scope is easy peasy. All you have to do is measure the diameter towards the lens area and divide it by 2.

There you have the scope height. As for the ring height, that depends on the manufacturer but in general, these change in increments of 4 which means the height can vary from anywhere between 26mm to 34mm and so on.

If you need better contact, I’d recommend going with vertically split rings.

Step 2: Mount Scope rings

To mount the scope rings, you should start by fixing the bottom rings. In some scopes, this part is as easy as screwing them on. Either way, the goal is to keep them straight but don’t overtighten them so you can adjust them later and get the alignment right.

The lapping kit has a lapping tool. Place it in the scope rings as it will help keep the rings perfectly aligned. Now you can tighten the rings further so they do not move due to recoil or other sudden movements 

Step 3: Position the scope correctly

Whether you are mounting the scope or lapping the rings, the scope needs to be placed on a stable surface. I prefer sandbags, but even a solid wooden table would work just fine. I prefer sandbags as they are cheap and I use them for my hunting trips as well, so helps me practice stabilizing the gun on a surface I intend to use in real-life situations.

You can also use vise grips or specialized rifle grips tailor-made to prevent the rifle from moving when working with lap bars. These grips are easier to use than sandbags and also ideal for when doing maintenance of your rifle and scope though keep in mind, these cost more as well.

Step 4: Apply the Lapping cream

Your kit will also include a lapping cream which needs to be applied on the insides of both the down and upper part of the rings. Just dab a little bit of the cream, as you do not want to go overboard with it for better performance. Oh, and don’t forget to get rid of the lapping bar either first.

Step 5: Place the Lapping bar

We removed the lapping bar in the previous step. Well, now it is time to put it to use correctly by inserting it into the rings and locking the upper portion of the rings.

Lock it tightly enough, so it comes in touch with the lapping bar but not so tight you cannot move it at all as it can damage the rings (a mistake a lot of beginners usually make).

Step 6: Move the bar back and forth

If you have tightened the rings perfectly, you should be able to move the lapping bar with ease. Now, move it back and forth into the rings but make sure it doesn’t fall out. Do this about 10-15 times as it will get rid of any burs that might be blocking the lapping bar. 

If the bar becomes looser after this, don’t worry just tighten the rings a tad. Once again, the goal is to tighten it just enough so it maintains a light grip on the lapping bar but not so tight that you have trouble moving it.

Step 7: Check on the Scope Rings

Once you have done the above steps 2-3 times, it is time to detach the scope rings and the lapping bar. Run your finger along with the ring surface and the bar to check if both surfaces are smooth enough. 

If you are using a premium quality rifle scope or have been maintaining it well, then doing the process for 2-3 hours should be more than enough but if not, you should get it right in another 2-3 attempts. 

Step 8: Mount the Scope

Are the rings as smooth as you had hoped them to be? If yes, it is time to assemble the scope back into place by firstly, attaching the scope rings. Start with the upper rings. In case you are wondering how tight it should be, check the manual as manufacturers usually recommend the tightness. 

But before you do that, give it a trial run and ensure the scope is leveled and is appropriately placed from your eyes. Don’t go overboard as the scope can get damaged, and it reduces performance as well.

In case the scope isn’t leveled, there are levelers you get with the kit that needs to be fixed on knobs. Once attached, continue to turn the knobs till they are flat. Once this is done, you should have no trouble zeroing with the scope. In case you didn’t already know, zeroing helps adjust the sight with the reticle so you can aim with 100% accuracy.

Few Tips to Keep in Mind When Lapping the Scope Rings

Measuring the scope height is important as it tells you whether the rings are compatible with it or not.

If your scope is bent, you are going to struggle with accuracy as the distortion impacts the barrel.

If you want your scope parts and tools to last you long, don’t forget to apply a thin coat of grease and store it all in a dry place as moisture can result in rust.

After lapping, make sure you give the cleaning ample time. If you rush it, there’s a good chance it will come back to haunt you the next time.

If the rings are not properly aligned, the pressure they apply on the scope will result in it bending. Thankfully, with a lapping kit, you have the power to check it now and then to ensure the longevity of the scope.

Don’t rinse your rings underwater straight away. You should wipe them with a dry paper cloth first.

Also, if you want good optics, make sure your rings have 4 screws to hold them down

Why You Should Lap Scope Rings

When you get a new scope, the rings that come with it are usually machined surfaces. But this machining quality isn’t that great, which means you might have some trouble using these rings across multiple scopes. Even if designed for that particular scope, you might still have trouble. 

That’s where lapping helps as it helps you adjust the shape of the inside of the rings and when the rings fit on the scope perfectly it improves both the durability of your scope as well as your accuracy.

Yes, it impacts durability as well. That is because it reduces the pressure on the scope due to which it doesn’t bend. Furthermore, your accuracy improved as the rings will sit perfectly on the scope and not move unless you want them to.

And it doesn’t matter whether you have a high-end scope or a budget rifle scope, they all need lapping although, with the cheaper ones, it will take you longer to get the shape of the rings right.


There’s everything there is to lapping scope rings the right way. It will boost your performance big time and will also increase the durability of the scopes. And once you know it, it will take you half the time to get the job done.

To top it all, all the tools are either provided with the scope or will cost you less than $100. In case you are stuck or have questions about which toolkit you should purchase, get in touch with me by dropping a comment below.

You can also get in touch with me using the contact form on the contact page. I’ll get back to you within 24-hours.

Oh, to end with, I’d also like to add that you should lap your rings even if the scope is meant for crossbows for the same reason. After all, who doesn’t want their scope to last long and help you aim with pin-point accuracy, right?

About Author

James Towndrow, a NRA-certified Firearms Instructor. During a career of 18 years had won several shooting competition including major leagues. Taking all those experience down the road, is now a successful Shooting Instructor in Texas, US.