How to Mount a Scope [2021]: 7 Steps to Installing A Riflescope the Right Way

by Ryan Cleckner

January 5, 2021

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If you’ve got a scope that needs to be mounted on a rifle but you’re not sure how to mount the scope the right way, you’re in luck.

Heck, even if your scope is already mounted on your rifle, there’s a good chance that it is either mounted incorrectly or it isn’t set up to fit you.

In this article we’re going to walk you through the rifle scope mounting process step-by-step. Steps to Mounting a Scope:

Step 1 – Gather the Right Tools

As with just about any project, having the right tools for the job is important.

In this first step to mounting a scope we’re going to provide a checklist of tools you’ll need.

We’ll also add some tools that aren’t absolutely required but are recommended because they either make scope mounting easier or ensure that the job is done better.

If working on firearms is something that you foresee yourself doing, go ahead and start picking up these recommended tools as your budget allows.

For more details about these scope mounting tools, including a discussion on the pros and cons for each option, see our deep dive into scope tools below.

Required Scope Mounting Tools:

  • Wrenches/Drivers for Securing Scope Rings and Rifle Base: Depending on your particular scope rings and base, you’ll either need a set of Allen Wrenches/Hex Keys, Torx Drivers, Screwdrivers, and/or, in some cases, sockets/wrenches.
    • Allen Wrenches/Hex Keys: A basic set of hex keys is all that is required. However, don’t go too cheap or you’ll regret it.
    • Torx Drivers: I like using name-brand Torx bits like these Bosch Torx Bits with a handled bit driver or torque wrench but simple Torx keys can work too.
    • Screwdrivers: Although any appropriately sized screwdriver could work, consider a hollow-ground screwdriver to protect your screws.
    • Sockets/Wrenches: Standard mechanic’s sockets or wrenches will work is required for the rings you choose.
  • Scope Leveling Tool: This handy scope leveling tool is superior to bubble levels in most cases and is used to help ensure that your scope is mounted level on your rifle.
  • Blue LoctiteThis semi-permanent thread locker helps to hold your mounting screws in place.

Recommended Scope Mounting Tools:

  • Torque Wrench: For mounting scopes, over-tightening screws can sometimes be just as bad as under-tightening. Torque wrenches that measure in inch pounds like the Magnatip Torque Wrench or Fix It Sticks, can be very handy.
  • Gun Caddy: A gun caddy, like the Tipton Gun Butler, helps to hold your rifle while you mount your scope.
  • Tool Tray: The Grypmat Tool Tray is one of those tools that you didn’t know you needed until you used one – it’ll protect your work surface and keep you from losing small parts.
  • Gun Oil: A good gun oil like Break Free CLP is useful to protect surfaces from corrosion.
  • Gun Solvent: If your parts aren’t clean, you won’t have a solidly mounted scope – using a good gun solvent like Shooter’s Choice Solvent is a good idea.
  • Beer or Whiskey: Upon successfully mounting your scope you can have a celebratory drink.

Again, if you’d like some help making decisions about which tools to get and you’d like to learn more, see our deep dive into scope tools below.

Step 2 – Select the Correct Rings and Base

If you don’t have the correct rifle base and scope rings, you’re not going to get very far with mounting your scope.

Rifle Base

The rifle base (sometimes called a scope base) is the part on top of the receiver of the rifle to which the scope rings attach.

On some rifles, the base is integral to the design of the rifle. However, on most hunting rifles, the base is a separate part that is attached to the receiver via screws. Examples of integral bases are the rails found on the top of an AR-15-style rifle (bottom) and on a Tikka T1X rimfire rifle (top) noted by red arrows in the image below:

Integral Rails / Bases on Rifles

Note how distinct the two rails in the above picture are – they are two completely different interfaces that MUST have scope rings of the same interface in order to work.

The AR-15 rifle has a “Picatinny Rail” whereas the integral rail on the Tikka is called a “Dovetail Rail.”  We’ll discuss more on base and ring interfaces below. Also note the screw-holes on the top of the Tikka rifle – these are for mounting a separate rail and therefore give the shooter a choice whether to use the integral Dovetail Rail or whether to mount a rifle base as a separate part. If you intend to mount a base to your rifle, you should ensure 3 things:

  1. The base is the interface style you want (and it matches your scope rings),
  2. The base is the proper elevation, and
  3. The base will fit your rifle.

Base Interface  Interface options for your rifle’s base will be explored in a bit so for now let’s cover the proper elevation for you base and whether it fits your rifle.

Base Elevation  Most bases, for most purposes, will have no elevation built-in. This means that the base is perfectly flat to the receiver and/or axis of the bolt. However, for long range shooting, it is often desirable to have a base with some elevation. An elevated base, for example a 20 MOA base, is higher at the back that it is in the front – in this example, it has a 20 Minute of Angle slope. If you’re not familiar with Minutes Of Angle / MOA, check out our article Understanding Minutes of Angle. For this article’s purposes, please just ensure that you have the elevation you want.

Base to Rifle Fit As far as the base fitting your rifle, you must confirm the base’s capability to fit your rifle. For example, a rifle base for a Remington 700 rifle with NOT fit a Savage 110 rifle.

Scope Rings

Your scope rings must be:

  1. The right diameter for your scope,
  2. The right height for your scope to fit on your rifle,
  3. The correct style for your needs, and
  4. The correct interface to mount to your rifle’s base.

As you can see from this picture of various scope rings, they can vary greatly in size, height, and style:

Various Scope Rings

Scope Ring Diameter A scope ring’s diameter is fairly straight-forward. The “ring” of the scope ring must be the correct size for your scope’s body. For example, a 34mm ring will not be suitable for mounting a scope with a 1″ diameter body. Scope Ring Height The correct height for your scope rings is not so straight forward. The rings must be tall enough to fit you particular model scope (especially the objective and ocular housings) on your particular rifle and barrel profile.  However, the rings must not be so tall that they make it awkward to shoot the rifle. Scope Ring Style Scope ring styles vary as greatly as styles of rifles. For example, you can get durable/beefy tactical style rings for hard use or lightweight rings meant for an ultra-light hunting rifle build. Both are great for their intended purpose and horrible for the other purpose. Scope Ring Interface As we’ve mentioned above, and will explore below, there are many possible interfaces for your scope rings and you should select the best style for your needs and you must select an interface style that matches your rifle’s base. To make matters slightly more difficult, there are even rings that don’t need a base and they mount directly to your rifle. In this way, the bottom of the rings are the base.

Base and Ring Interface

There are many interface options for your scope rings and rifle base for your rifle and although some styles overlap their purposes, some interfaces are particularly suited for a particular need or use. Here are some popular interfaces and what they’re best for:

InterfacePurposeProsCons
PicatinnyTactical and/or Precision ShootingStrong, Many mounting locations, Very commonHeavy, Bulky
DovetailHunting, Rimfire, Small RiflesSimple, lightweight, Many positions (front and back)Not very strong
Cross-Slot/UniversalHunting, PlinkingInexpensive, CommonNot very strong, Limited mounting positions
IntegralHunting, Lightweight riflesLightweight, SimpleLimited mounting positions
"Standard"Hunting-Limited mounting positions, Old system
Quick ReleaseHunting rifles with iron sightsCan be removed quickly to use iron sights as backup.Limited mounting positions, not the most stable

Whichever you choose, don’t forget to make sure that the interface for the rings and base match!

Step 3 – Mount the Base to Your Rifle

If you are using a separate base (instead of an integral base that is already part of your rifle), it is time to mount the base to the rifle’s receiver. If, however, you are using an integral base, you may skip this step and move along to Step 4.

Prep Surfaces: First, ensure that the bottom of the base and the top of the receiver are clean. A simple wipe with some gun solvent and a clean cloth are all that you should need.

Next, I like to apply a very thin coat of Break Free CLP to the bottom of the base and the top of the receiver for rust prevention – it should be many years, if ever, before the base is removed.

Once the surfaces are prepped, it is time to install the base onto your rifle.

Test-fit Base: Ensure that the base (or bases if using a two-piece base) is/are oriented properly (if using an elevated base, the thinner end is forward) and tighten the screws through the base and into the rifle finger-tight (barely snug) to ensure a proper fit.

After you’ve confirmed the fit of the base, operate the bolt/action to ensure that the base screws are not sticking through the receiver and interfering with the bolt (it happens sometimes).

Final Installation: Remove one base screw, apply a half drop (if possible) of blue Loctite to the threads of the screw, and reinstall the screw before moving on and repeating the process with each additional screw one at a time.

If you’re using an hex-key or torx key only, I like to install the screws with the long-end in the screw and the short-end in my fingers for leverage so that I don’t over tighten the screws.

If you are using a torque wrench (the best way to do this), you should not exceed 25 inch pounds and, in most cases, I use 20-22 inch pounds.

Step 4 – Attach the Scope Rings to Your Base

Attach the rings to the base before clamping the rings onto the scope. We do this because the base, and not the scope, will determine the spacing of your rings.

If your base allows for multiple mounting positions, try attaching each ring a couple of positions in from each end as a starting point.  The final position of your rings may change throughout this process (especially after the next step). If you determine that it is necessary to change the position of the rings, you should come back and complete this step before moving on.

Attaching Rings to Base:  Attach the rings to the base with the adjustment mechanism on the opposite side of the ejection. For example, on a right handed rifle (right side ejection), I prefer to orient the rings so that the adjustment nut or screw-heads are on the the left side of the rifle.

For most bases and rings, you should notice a small amount of front to back movement (slop) between the rings and base before tightening the rings. You must ensure that the rings are pushed forward before (and while) tightening so that the rings are in the most forward position of the slop/slack.

During firing, inertia will cause the rings to move forward relative to the rifle and by having them at their forward limit already, you’ll reduce their possibility of them moving once installed.

There is no need to torque the rings down at this point – finger tighten them only for now as you may need to move the rings during the next step.

Insert Scope into Rings: Next, place the scope into the bottom half of the rings (this is where the rifle caddy we mention above is really handy to hold the rifle) and then LOOSELY attach the top half the rings so that the scope can freely move within the rings.

This part is important to keep the scope from falling off your rifle and hitting the floor. Don’t ask how I know this can happen.

Step 5 – Adjust the Scope’s Position to Fit You

Take the time now to adjust the scope forward and back until you can see a perfectly clear image (no fuzzy black ring around the edge of your view) while in a comfortable firing position.

To do this properly, you should get into a typical position that you intend to fire this rifle and then place your head onto the stock of the rifle with your eyes closed to find a comfortable position. Only after you are in a comfortable position should you open your eyes to determine if your scope is in the correct position.

Too often, without realizing it, shooters will move their head to see clearly through the scope instead of the other way around. This often results in less than desirable shooting performance and a fatigued neck or shoulders.

For many of you, this will be an “Aha!” moment as you realize you’ve been scrunching your neck for years.

Move the Scope: If you see anything but full light around the entire scope lens, you either need to move the scope forward or backwards or your head up or down.

A forward or backward adjustment is easy – you simply slide the scope until all of the black fuzzy ring has disappeared. You may find that the position of the rings needs to be adjusted in order to get the scope where it fits you. Do not panic. Move the rings to where they and then follow the previous step before coming back to this step to confirm the scope’s position.

If you need to adjust the height of your head relative to the scope, you can either use different height rings or adjust the cheekpiece (comb) of your stock.

Here’s a video I made for the National Shooting Sports Foundation quite a few years ago (pre-beard) that might help you here:

Lightly Tighten Scope Rings Onto Scope: Once the scope is in the correct position, you can LIGHTLY tighten the scope rings around the scope to help hold it in place.

After all, you just got it into the proper position and you don’t want it to move.

Keep the rings loose enough, however, to rotate the scope to level it in the next step. A small amount of friction is all that is needed now to prevent accidental movement.

Step 6 – Level Your Rifle Scope

Most rifle scopes have a flat bottom that can be used to align the scope with the rail on the rifle.

Leveling flat-bottomed Scopes: Using the Scope Leveling tool we recommend above, put the base of the tool on the rail and use one of the tool’s wedges (there should be a low and a high wedge) to align the flat bottom of the scope body to the rail.

By having the rings loose enough that the scope can be rotated, you should be able to insert the tool’s wedge so that the scope rotates and aligns itself.

Once level, finger-tighten the scope rings.

It’s that easy.

That is, of course, unless you want to use all sorts of bubble levels and gadgets. In that case, be prepared for a long process here that includes repeating everything more than once as you think it’s level based on your gadgets only to look through the scope and see a crooked reticle.

Here’s a video that shows you how to use the tool to level your rifle scope:


Leveling round-bottomed Scopes: These types of scope are much more difficult to level. Thankfully, these types of scopes are fairly rare.

You can either use a series of levels to level the rifle first and then level the scope by placing a level on the top scope cap, or you can do your best to “eyeball” it.

Do not be fooled into a false sense of confidence by using something like a plumb bob hanging on a string. Yes, this can ensure that your reticle in the scope is perfectly up and down, however, this will only help you if you are 100% sure that your rifle is perfectly level before tightening the scope rings.

Step 7 – Secure the Rings to the Rifle and Scope

Tighten Rings on Rifle: Now that you are sure the rings are in the correct position, you can fully tighten the scope rings to the base.

For tactical and heavy duty rings, I use 65 inch pounds. However, for hunting-grade rings, I don’t like to exceed 25 inch pounds.

Tighten Rings on Scope: Now that the scope is in the correct position within the rings and it is level, you can fully tighten the rings around the scope.

Tighten the rings around the scope by turning the screws in an X pattern (similar to changing a wheel on a car) while ensuring that the gap on each side of the rings is similar.

BE CAREFUL HERE to not over-tighten these screws.

This is where a lot of folks get into trouble by putting too much torque on these screws. With some scopes, you can actually change the performance of the scope.

I like to use 15 inch pounds of torque on the scope ring screws for most scopes. If the scope is really heavy duty and it’s going on a heavy recoiling rifle, you can go up to 20 inch pounds if you’d really like. Here are the torque settings I like to use:

Scope Mounting ComponentPreferred TorqueMaximum Torque
Rifle Base20-22 in/lbs25 in/lbs
Tactical rings to base65 in/lbs65 in/lbs
Hunting rings to base20 in/lbs25 in/lbs
Scope rings around scope15 in/lbs20 in/lbs

Apply Thread Locker: Once everything looks good, you can now apply thread locker to the scope rings. One by one, just like with the base, remove each scope ring screw and apply a half drop of blue Loctite and reinstall the screw to the proper torque.

Zeroing Scope / Sighting in Rifle

Now that your scope is mounted to your rifle, you need to zero the scope/sight-in your rifle.

If you’d like some help with this, you should go check out our article: How to Sight in a Rifle

Why a Scope Must Be Mounted to Fit the Shooter

Here’s my favorite analogy to illustrate why a scope must be positioned on a rifle to fit the shooter: If a driver’s seat, steering wheel, and mirrors of a car are not properly adjusted to fit the driver, then the driver will get less than optimum results no matter the driver’s skill nor the performance capabilities of a car.

The same is true with your rifle and scope.

Even if the scope was mounted from the factory or a competent gunsmith, the scope may be properly mounted to the rifle but there’s no guarantee that it will be properly set up to help you achieve the best results when shooting.

Does this mean that you can’t shoot someone else’s rifle effectively? No!

In fact, there’s a great chance that if you’ve been shooting for a long time that you have plenty of practice shooting improperly adjusted scopes on rifles.

However, even though similar sized shooters may be able to use each other’s equipment, it is true that a large adult will probably find it very difficult to shoot a rifle with a scope mounted for a smaller child.

As a sniper instructor for many years I’ve encountered so many incorrectly mounted, or improperly fitting, scopes on rifles that I start every long range shooting class with re-mounting scopes the correct way to fit the shooter.

Proper scope mounting is crucial: If the scope is mounted incorrectly, the rifle won’t achieve its best performance. If the scope isn’t set up to fit you, then you won’t achieve your best performance.

Tools for Mounting Scopes – Deep Dive

To properly mount your scope, you’re going to need the right tools.

We are going to recommend the basic tools needed for mounting a scope and also give some recommendations for specialty tools that make the job much easier and faster.

Also, we’ll cover some optional tools that you might find handy but that we don’t necessarily think are needed. There are three categories of tools for scope mounting:

  • Tools for your workspace,
  • Tools for tightening parts,
  • Tools for leveling your scope, and
  • Solvents, oils, and thread lockers

Tools for your workspace

When mounting a scope to your rifle, you aren’t going to be hammering nor cutting anything (you shouldn’t be anyway) so any stable table or bench will work.

However, for your workspace, it is very handy to have something to help hold your rifle while mounting the scope and all something to help hold your rings, base, (their screws), and any tools.

For holding your rifle while putting on your scope, and for other maintenance and cleaning, we really like the Tipton Gun Butler as a rifle caddy. The Tipton Gun Butler helps to hold your rifle and it has space in the middle to help holds tools and solvents.

There are other fancier gun caddies but we think this one is the best because it is so inexpensive and it is just the right size for home firearm maintenance – it doesn’t take up too much space on a workbench and it can fold flat for easier storage.

Another tool we really like for your workspace are Grypmats. The make holding tools and parts handy AND they help to protect your surface from dings and dents (helpful if your workspace is your kitchen table). Try one of these and you’ll know what we mean – organizing tools and those little screws in scope rings is really handy.

Tools for tightening parts

Mounting your scope will likely involve tightening a base to a rifle with screws, tightening cross-bolts or screws on the bottom of the scope rings to the base, and tightening the rings around the scope body.

Most of these screws will be Torx (the star shape) or Allen head (hex key) but some rings and bases be tightened with flat-head screws. Also, if you’re dealing with heavy duty tactical style rings, you should expect 1/2″ nuts to tighten rings onto the base.

Yes, household tools could work here.

There is really no “need” to get specialty tools for the various screws (especially if mounting a scope is a one-tie thing for you). However, as with most things in life, having the right tools for the job will make it easier AND it’ll protect your rifle and parts. If you use cheap Allen or Torx bits, you’re eventually going to break them.

If you use household or mechanic style screwdrivers, you’re likely to damage screws on your gun. Why? Standard screwdrivers are tapered to make them easy to insert into the slot of a screw head. The problem with this is that the pressure is put on the very top of the screw where it is weak and easy to damage.

Hollow-ground bits, on the other hand, are made specifically for this and may be a bit more snug to insert into a screw head but they apply pressure at the base of the screw slot where it is strong and protect your screws from being damaged or stripped.

Fortunately, there are some sweet tool kits you can pick up to make your life easier. A Brownells Magna Tip set is a GREAT investment to start your home gunsmithing adventures. It consists of 24 true hollow-ground bits and a screwdriver handle that will come in handy in just about every gun maintenance situation you can think of. The Brownells Magna Tip set also makes for a great gift for any gun owner and enthusiast. If you’re looking for a good set of Torx bits, I’ve found the best luck with name-brand Torx bits for impact drivers like this Bosch Set.

Bosch is known worldwide for their quality standard. And while these aren’t going to be the cheapest Torx set you’ll find, you can at least count on them to not break when turning through thread-locked screws.

Another tool that isn’t necessary for the occasional hobbyist but that is SUPER handy if you can afford it, is a good torque wrench. I’ll give some tips below that I use to avoid over-tightening scope rings onto a scope body but if you’re wanting to do this the right way, and you plan on working on other guns, go ahead and get a torque wrench now.

For torque wrenches, you need a small one suitable for scope and guns (not giant ones for cars). You’ll need a torque wrench that adjusts in inch pounds and not foot pounds. My two favorite torque wrenches for mounting scopes are the Magna Tip torque wrench which is best for gun-bench use and a set of Fix It Sticks which are great to take along with you to the range.

Tools for leveling your Scope

If you’re one of those shooters that swears by using multiple sets of bubble levels and even hanging plum-bob line to level your scope, I’m not going to stop you.

MANY shooters treat leveling their scope like it’s a mystical process and may even consult a quija board or sprinkle magic sniper fairy dust over their scope as they level it.

However, I think these things are unnecessary at best and, at worst, give a false sense of confidence and result in a crooked scope.

The vast majority of scopes I use have a flat bottom which makes a tool like this scope leveling tool perfect. It’s simple, it’s fast, and it works. I swear by the Arisaka Scope leveling tool.

Solvents, Oils, and Thread Lockers

If you don’t have a good gun oil already, you need to get one. If you need help knowing which is the right one for you, check out our Best Gun Oil guide.

Having a good solvent is also handy to clean off any surfaces while you’re working. (shooters choice solvent link) Having blue (NOT red) Loctite is a must to properly mount your scope. Blue Loctite is a strong hold that can be removed as needed – red, which should be avoided for scope mounting, is “permanent.”

Other Tools

Some people swear that rings must be “lapped” prior to mounting a scope.

I think that this is hogwash.

Lapping rings involves using hand tool to polish and align the inside diameter of the scope rings to ensure they are true to each other and perfectly round. If this really matters to you (I consider myself a rifle expert and I’ve never done it nor had the need to) you are likely chasing an amount of precision where such a thing would matter.

Yes, cheaper rings can not be perfectly aligned and hand lapping would solve this. However, if this level of precision matters to you, why are you using cheap rings? Instead of hand lapping tools and labor (during which it is easy to ruin your rings) why not just buy a set of quality rings that don’t need to be lapped? Those of you that would like to argue with this, knock yourselves out in the comments below.

Recommended Tools Recap:

ToolUseCheck Price
Tipton Gun ButlerGun WorkstationCheck Price
GrypmatTool CaddyCheck Price
Brownells Magna Tip SetHollow-ground screwdriver setCheck Price
Bosch Torx SetFor ring and base adjustmentsCheck Price
Magna Tip Torque WrenchProperly tightening scope mountsCheck Price
Fix It SticksRepairs on the goCheck Price
Arisaka Scope Leveling ToolLeveling your scopeCheck Price
Shooters Choice SolventCleaning work areasCheck Price
Blue LoctiteRemovable threadlockerCheck Price

Scope Mounting FAQ

What type of Loctite, if any, should be used on scope rings and bases?

Only blue Loctite should be used on scope rings and bases as it is not a permanent hold.

Is it necessary to “lap” rings when mounting a scope?

No, it is not necessary to lap scope rings. Yes, it can ensure that the rings are true, however, you should buy quality scope rings that do not need lapping and still save money over buying a ring lapping kit.

Can I over-tighten my scope rings?

Yes, it is very easy to over-tighten scope rings on to a scope. Too tight of rings can actually impede a scope’s ability to function.

What torque setting should I use when tightening my scope’s rings?

  • Rifle base screw torque should not exceed 25 in/lbs.

  • Scope rings should not be torqued to the base greater the 65 in/lbs for tactical rings and 25 in/lbs for lighter hunting rings.

  • Scope rings should not be clamped around the scope with a torque greater than 20 in/lbs.
  • What is the best torque wrench for rifles and scopes?

    The best torque wrench for rifles and scopes is either the Magna Tip Torque Wrench (for workbench use) or Fix It Sticks (for use in the field).

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    About Ryan Cleckner

    Ryan is a former special operations sniper (1/75 Ranger) and current firearms attorney, firearms industry executive, university lecturer, and bestselling author of the Long Range Shooting Handbook.

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    1 COMMENTS

    1. I can’t thank you enough Mr. Cleckner. All of your amazing lessons have helped and inspired me a great deal. You are an amazing teacher!

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