Mounting a rifle scope or AR15 optic correctly is essential for maximizing accuracy and performance.
In this installation guide, our Ammunition Depot firearms expert, Matt, walks you through each step to ensure a seamless setup.
From selecting the right tools to carefully aligning the scope, we cover everything you need to know for a successful installation.
Remember, safety comes first—always ensure your firearm is unloaded before beginning.
With patience and the right approach, you'll have your optics mounted perfectly, ready to enhance your shooting experience.
Installation Overview
In this video installation guide, our Ammunition Depot firearms expert Matt gives you a step by step breakdown on how to properly mount a scope on your rifle to maximize its performance!
From the initial setup to the necessary tools and hardware needed, we’ve covered all the steps to get your newly purchased rifle optic successfully installed.
Safety Precautions
Before you begin your installation, the most important thing to remember is SAFETY!
Always ensure that your rifle, handgun, or firearm is unloaded and the chamber is empty with the magazine removed.
Once cleared, you're now clear to begin the installation.
Remember to go slow and to be patient throughout the process - the last thing you want to do is ruin your new scope or have to re-do the entire process.
How-To Mount AR15 Optics Video
Tools Needed to Mount a Rifle Scope
Hex Bit Tool
Perfect for increasing turning power and stability, a hex bit tool/set can be very useful for performing routine maintenance or installations on your rifle or firearms.
Torque Wrench
Whether you're installing a scope or making fine adjustments to your firearm, a torque wrench can save you time by accurately torquing screws to spec.
Bubble Level
Ideal when installing a scope or optic sight, a bubble level will help ensure your accessories are completely level and can eliminate the need for remounting or making adjustments after the installation is complete.
Rubbing Alcohol or Cleaning Patches
Keeping your rifle, scope, or optic clean before mounting is critical to ensuring no dirt or debris hinders the hardware.
Gun Vice
Vices are an absolute must when working with firearms. They keep your hands free to complete whatever work is necessary while keeping your rifle/pistol securely stable.
Common Mistakes to Avoid
Mounting a magnified optic on your AR rifle may seem straightforward, but small missteps can lead to poor performance or even damage.
Here are some of the most common mistakes to avoid when setting up your optic:
Incorrect Eye Relief Placement
One of the most frequent issues is mounting the optic too far forward or too close to the shooter’s eye. This can cause a distorted sight picture or scope shadow, reducing your field of view and slowing target acquisition.
Always test your eye relief in your actual shooting stance before tightening everything down.
Not Leveling the Reticle
If your reticle isn't perfectly level, your shots will drift off target—especially at longer distances.
Use a bubble level or reticle leveling tool to ensure your scope is properly aligned with your rifle's bore axis.
Over-Torquing Mounting Screws
It’s tempting to crank down the screws to keep things secure, but over-torquing can strip threads or deform your scope tube.
Follow the manufacturer's torque specifications and use a torque wrench for precise installation.
Using the Wrong Mount or Rings
Not all scope mounts or rings are created equal. Using mismatched or low-quality mounting hardware can cause stability issues or damage your optic.
Choose mounts that are specifically designed for AR platforms and match the tube diameter of your optic.
Ignoring the Importance of Loctite
Failing to apply a small amount of non-permanent thread locker (like blue Loctite) can result in screws backing out over time due to recoil.
Just don’t use permanent adhesives, as they can make future adjustments a nightmare.
Neglecting Zeroing After Installation
After mounting your optic, always re-zero it—even if it’s replacing a similar one. Each optic and mount combo can affect point of impact.
Skipping this step will lead to poor accuracy downrange.
Mounting Too High or Too Low
The height of your optic can affect comfort and shooting accuracy. Too high, and you’ll experience neck strain or inconsistent cheek weld. Too low, and you may not clear other rifle components or get a clear sight picture. Aim for a natural, repeatable cheek weld aligned with the optic.
Avoiding these mistakes not only improves accuracy and performance, but also protects your investment in quality optics and rifle components.
Take your time, double-check your setup, and when in doubt—consult a professional.
Summary
Much of the information throughout the video and throughout this article will apply to any modern rifle scope, AR scope, magnified optic, and most any modern rifle platform.
However, it's always best to err on the side of caution and review both your firearm and scope/optic owner's manual before starting the installation process.
Don't have a scope or optic to mount?
Not to worry, at Ammunition Depot we carry a wide selection of firearm optics including scopes, red dot sights, and thermals to mount onto your rifle or AR.
We also carry a wide selection of Firearm Cleaning Supplies and Gun Tools to help you get the job done quickly and efficiently!
