is reader-supported. When you buy through links on my site, I may earn an affiliate commission. For more details Click Here.

How to Mount a Scope on AR-15 with Front Sight?

How To Mount A Scope On AR-15 With Front Sight?

An AR-15 rifle is a semi-automatic rifle which is based on ArmaLite AR-15 design. ArmaLite is a scaled-down derivative of Eugene Stoner’s AR-10 design. However, currently, AR-15 is used as an umbrella term for all semi-automatic rifles. 

A host of gun makers make rifles on this design. The nomenclature is based on the original manufacturer’s name ArmaLite Rifles. People tend to confuse it with ‘assault rifle’ or ‘automatic rifle’. 

How To Mount A Scope On AR-15 With Front Sight

ArmaLite developed it as a military rifle in the late 1950s but failed to score success in the market. ArmaLite then sold patents to Colt who started manufacturing in 1959. By 1963, the U.S. military chose Colt to manufacture its rifles, which Colt sold under the name M-16. 

Over time, Colt developed a semi-automatic version of M-16, which was sold to law enforcement and the public by the name AR-15. When in 1970, the patent rights of Colt expired, other manufacturers also started its manufacturing. 

Tools required to mount a scope on AR-15 

Tools required to mount a scope on AR-15

Before mounting a scope on the AR-15 rifle we need to understand that it is not the same as mounting a scope on a regular rifle. 

An AR-15 has high accuracy and good quality metal used because of its utility in military services. Proper care should be taken while mounting a scope on a rifle of this kind. 

You don’t want to affect the accuracy and metal by mounting a scope incorrectly. Here are some tools that you might require while mounting a scope on AR-15 with the front sight. 

A Torque wrench: This is a necessary tool to mount a scope on an AR-15. It is also a good tool to have in your toolbox too!

Bubble level: A bubble level is necessary to maintain an accurate level while installing the scope. The bubble level will help to maintain the accuracy and precision of the optic.

Shooting rest: It also goes with the name gun vice. This is used to place the rifle and also to check the accuracy of the scope. A bit of investment in a shooting rest will prove beneficial for all your future endeavours. 

Rubbing alcohol and microfiber cloth: This is used to clean the parts of scope and rifle before installing the scope.

Hex Bit too: This is pretty much used for the installation of scope on rifles, not specifically for an AR-15. It is also a necessary tool to have in your toolbox. 

A cantilever scope mount: This scope mount is better than normal scope mounts and when it comes to using it for AR-15, nothing can beat it.

How to mount a scope on an AR-15 with front sight?

Now that you have your rifle and rifle scope ready and have gathered necessary tools to install the scope, all you need is patience to fix the scope on the rifle. 

We don’t want to rush through the process because you might end up having to re-do the whole process again. And worst-case scenario, your rifle or scope might get ruined!

Prepping the AR-15 for the process: Place the scope on the shooting rest or gun vice. Lay it carefully and securely before starting to work on the rifle.

Cleaning the parts: Pour the rubbing alcohol on the microfiber cloth and clean the parts of the rifle by gently rubbing the parts. Also, clean the scope and the mounting base. It would help to remove excess oil from the surface making it easier to mount the scope.

Place the scope mount: After a thorough cleaning of the rifle and the scope, it is time to place the scope mount on the rifle. This is an important step because if the mount is placed incorrectly then it would cause unwanted stress on the tube. 

Avoid placing it on a free-floating rail and upper receiver collectively, it would burden the tube.

Firstly place the scope mount on the rifle and tighten it with your hand to make it stable. Once the mount is stable take the torque wrench and tighten the screws to its place. Don’t over tighten it, as every mount has a different torque level. 

Placing the scope: After all the fundamental steps to install the scope has been done it is time to place the scope. The scope should be placed correctly so that you have enough space to move the optic and also the scope’s body is perfectly balanced. 

Place the scope on the mounting base so that scope’s body is laying flat to the rings. The top portion of rings should be consistent with the optics of the scope. When tightening the rings it should make an ‘X’ pattern.

Avoid over-tightening the rings and there should be some gap level as it would make the scope durable to recoils. 

Levelling all the parts: The first thing to do here would be to check the eye relief is in a suitable position or not for you. 

Now, place the bubble level on the flat part of the rifle tube. If your rifle is not placed on the shooting rest then firstly place the rifle on a stable surface where it is properly levelled. 

Make sure that reticles are aligned vertically as well as horizontally. Once it is done place the bubble level over to the same level as the optics.

Final touches: Now as everything is levelled, tighten the scope by filling up the gap left earlier by making ‘X’ patterns again on both sides of the scope. Clean it with a cloth or a soft-bristled brush and now you are ready to go for a shooting. 

Frequently asked questions

Q: What is a front sight?

A: It is an optical device or a piece of metal on either breech or the muzzle of a rifle. In layman terms, it is a sight closest to the muzzle.

Q: What is a cantilever scope mount?

A: A Cantilever scope mount is highly suggested for an AR-15. It has two sets of rings to fit Picatinny weaver rails. 

It is said to be better for such a genre of the rifles because it has certain advantages over regular scope mounts. It gives the shooter more rail by pushing the optic forward. This helps the magnifier to fit behind. The scope mount changes the centre of balance giving stability to the scope and allowing accuracy and precision. 

Q: Is AR-15 suggested for hunting? 

A: it can be used for hunting but it is not a hunting rifle. It has 223 calibre ammunition and it does not offer much-stopping power. It can be used for a small game tho. 

Q: Which other companies manufacture AR-15 style rifles?

A: Many other companies build AR-15 style rifles other than Colt. Some of them are: Bravo Company, Daniel Defense, Noveske, Rock River, FN Herstal, LaRue, LMT (Lewis Machine & Tool)

People prefer Colt’s AR-15 because of its authenticity of the rifle but many other companies also have developed their rifle on the same lines as AR-15.

Q: What can be used instead of a Cantilever scope mounts?

A: you can always use scope rings instead of scope mounts. Scope rings are traditionally used to mount scopes. 

The cantilever scope mount provides extra rail and stability to the scope otherwise scope rings are also a really good option. Rings are lighter than one piece mounts and they come in different heights hence giving the wider range for shooters to choose from.

Choose a scope with good eye relief. If the eye relief is not good you may get hit with the scope during recoil. A higher cost doesn’t always mean it is the best option. Sometimes scopes and rifles are expensive and don’t provide value for money.

Always clean the scope and maintain it thoroughly. It would make your rifle and scope last long. Make zeroing in a habit. This allows you to maintain the level of scope, and don’t ever rush on any process. 

Be patient while mounting the scope and cleaning parts. Sometimes rushing up the process may end up ruining a good scope and rifle. 


AR-15 is a semi-automatic lightweight rifle which is best suited for military purposes. It has high accuracy and is considered among one of the best rifles. 

Proper care should be taken while mounting a scope on it. However, it is true for regular rifles too. The scope mounting on any kind of rifles should be done patiently and carefully. 

Always clean the excess oil off the surface before mounting the scope. Use a bubble level or pair of bubble levels to level the scope. Check the horizontal and vertical alignment of reticles too.

Leave a Comment

Your email address will not be published.