Gathering Your Arsenal of Tools
Essential Screwdrivers
First on the list is a collection of screwdrivers. Different scope rings and mounts use varying screw sizes, so having a set of quality screwdrivers, including both Phillips head and flathead options, is crucial. Ensure the screwdrivers fit snugly in the screw heads to prevent stripping or damage.
The Indispensable Torque Wrench
Next, a torque wrench. This is perhaps the most critical tool in the entire process. Scope rings and mounts often have recommended torque specifications, and a torque wrench ensures you tighten the screws to the precise level required. Over-tightening can crush the scope tube, while under-tightening can lead to the scope shifting during recoil, negatively affecting your accuracy and potentially damaging the scope. Invest in a torque wrench that covers the range of torque specifications typically found for scope rings.
The Leveling Essentials
A level is another essential component for a successful scope mounting. A bubble level, a scope leveling kit, or even a combination of both, is very useful. Ensuring your reticle, the crosshairs or aiming point within the scope, is perfectly level is paramount. Without a level reticle, your shots will be off, and your accuracy will suffer. The level helps you to make sure the rifle is level before you tighten the scope rings.
Allen Wrenches for the Task
Depending on the rings or mount you choose, you might need Allen wrenches. Many mounts use Allen screws, so a set of high-quality Allen wrenches will be necessary. Make sure these are the correct size to avoid stripping the screws.
Maintaining Clarity with Cleaning Supplies
Always remember to include cleaning supplies. Lens cleaner and a high-quality lens cloth are necessities. Smudges, fingerprints, or dust on the lenses will degrade your view. Cleaning your lenses ensures the brightest, clearest sight picture possible.
Securing the Hardware: Thread Locker Consideration
Finally, Loctite or thread locker can be helpful. Some shooters choose to use thread locker on the screws to further secure them. However, consult the manufacturer’s recommendations for your specific rings or mount, as thread locker isn’t always necessary, and it can sometimes make adjustments more difficult.
Assembling Your Arsenal: The Materials You Need
The Heart of the System: The Scope
The primary material, of course, is the scope itself. Selecting the right scope for your AR-15 depends on your intended use. Consider magnification, objective lens size, reticle type, and intended shooting distances. The right scope makes all the difference.
Bridging the Gap: Scope Rings or Mounts
Next comes the scope rings or scope mount. This is the interface between your scope and your AR-15. There are different types: two-piece rings, one-piece mounts, and cantilever mounts. Research the best option for your scope’s tube diameter and the type of rail on your AR-15 (most modern AR-15s have a Picatinny rail). These rings or mounts need to be compatible with your rifle and scope.
The Foundation: Your AR-15 Rifle
Obviously, you’ll need your AR-15 rifle. Ensure it’s in good working order and that you have access to a safe and appropriate workspace.
Rails and Compatibility
Consider whether your rifle has a Picatinny rail. While many AR-15s come with a Picatinny rail, some older or specialized models may not. If yours doesn’t, you’ll need to install one.
Preparing for the Assembly: Your Rifle and Your Scope
Unloading for Safety
The most crucial step is to confirm your AR-15 is unloaded. Safety is paramount. Remove the magazine, open the bolt, and physically inspect the chamber to ensure it is empty. Cycle the charging handle several times to ensure there are no rounds present. Double-check. Then triple-check. Never take a firearm for granted.
Scope Inspection
Now, let’s inspect the scope itself. Examine the scope for any signs of damage, such as scratches or dents. Familiarize yourself with the scope’s adjustments, including windage, elevation, and parallax (if applicable). These are critical to zeroing the scope later.
Lens Care
Take a moment to ensure the scope’s lenses are clean. Use your lens cleaner and cloth to remove any dust, fingerprints, or smudges. A clean lens provides the clearest possible image.
Rings/Mount Compatibility Check
The rings or mount must be compatible. Before you begin mounting the scope, confirm the rings or mount’s compatibility with your scope’s tube diameter and the type of rail system on your AR-15. Most scopes use a one-inch or thirty-millimeter tube. Make sure you have the correct rings. Also, ensure that the rings or mount are designed for use on an AR-15.
Putting It Together: Mounting the Scope Step by Step
Mounting to the Rail
First, attach the rings or the mount to the rail on your AR-15. The Picatinny rail, typically found on the top of your AR-15’s receiver, provides the foundation for your scope. Secure the rings or the mount to the rail following the manufacturer’s instructions. Ensure the clamps or screws engage properly.
Torque Specifications
Tighten the rail clamp screws to the recommended torque specification. Use your torque wrench to ensure you don’t over-tighten or under-tighten. Over-tightening can damage the rail or the mount, while under-tightening can cause the mount to shift during firing.
Inserting the Scope
Next, insert your scope into the rings or mount. Loosely tighten the top halves of the rings, just enough to hold the scope in place but allow for adjustment. Don’t tighten them fully yet.
The Art of Leveling
This is the stage when leveling the scope is critical. There are various methods for leveling the scope:
Using a Leveling Kit: These kits often have a small level that fits into the scope’s tube and another to place on top of the receiver.
Using a Bubble Level and the Rifle: Place a bubble level on a flat, level surface (like a table). Then, place the rifle on the table and position the scope so that the reticle is level and the rifle’s receiver is perpendicular.
Using a Level and a Plumb Line: Hang a plumb line in front of the rifle. Align the vertical crosshair of the scope with the plumb line. Then, level the scope relative to the rifle.
Adjust the scope’s position within the rings until the reticle is perfectly level. Make sure the crosshairs are aligned with the vertical and horizontal lines. This is probably the single most important step.
Secure Tightening
With the scope leveled, it’s time to torque the ring screws. Use a torque wrench and tighten the ring screws to the manufacturer’s recommended torque specifications. Tighten them in a criss-cross pattern. This is very important. Alternating between screws ensures even pressure on the scope tube.
Eye Relief
Now, position your scope for optimal eye relief. Hold the rifle in a normal shooting position. Move the scope forward and backward until you achieve a clear, full field of view. Eye relief is the distance between your eye and the scope’s eyepiece when you get a full view. Make sure you have enough distance to avoid recoil-related injuries.
Final Checks
Double-check everything. Ensure all the screws are properly torqued. Inspect the scope’s position and alignment again. Make sure the scope is still level and the reticle is still aligned. Clean the scope’s lenses one last time.
Essential Considerations and Expert Advice
Eye Relief Importance
Understanding eye relief is critical. The correct eye relief ensures a clear and comfortable sight picture, and it helps to prevent “scope bite,” where the scope recoils into your eye. The proper eye relief distance will vary from scope to scope.
Torque Wrench: The Cornerstone of Stability
The torque wrench is not just a tool. It’s an insurance policy against scope damage and shifting.
Zeroing at the Range
After mounting your scope, the next step is zeroing at the range. Take your AR-15 to a safe range, and adjust your scope’s windage and elevation to align the point of impact with your point of aim. There are plenty of guides on how to zero your scope, so take time to understand this.
Making the Right Choices
Choosing the right scope and mount is important. Consider your intended use of the AR-15. Different scopes have different magnification ranges and features. Make sure to choose a scope that suits your needs and budget. Consider the quality, durability, and your shooting style.
Mounts and Rings
The mount or rings you choose also play an important role. One-piece mounts are generally more robust and offer more inherent stability than two-piece rings. Cantilever mounts, which extend forward from the receiver, are often used to provide additional eye relief. Consider what works best for your needs.
Platform-Specific Modifications
Remember that different AR-15 platforms may require modifications. Rifles that use a gas piston system can generate more vibration that may impact the scope.
Dealing with Challenges: Troubleshooting Common Issues
Leveling Challenges
If your scope isn’t level, loosen the ring screws and re-level the scope. Double-check your leveling tools and ensure your work surface is also level. Re-tighten the ring screws to the correct torque.
Maintaining Zero
If your scope won’t stay zeroed, check the following: Are the rings or mount securely attached to the rail? Is the scope properly secured in the rings? Are the ring screws tightened to the correct torque specification?
Stripping Screw Problems
Stripping ring screws is a common problem. If this happens, you likely overtightened the screw. Replace the stripped screw with a new one.
Eye Relief Issues
If you are having trouble with eye relief, change the position of the scope in the rings to make sure you have a full view of the reticle.
Final Thoughts and Your Path to Accuracy
Mounting a scope on an AR-15 is a rewarding undertaking. It’s a skill that opens up a new level of precision and enjoyment. By following these steps, you’ll be well on your way to mounting your scope correctly.
Remember, the quality of your shooting experience depends on your attention to detail. Take your time, double-check your work, and never compromise on safety.
Now that you’ve learned how to mount a scope on an AR-15, go out and enjoy your newly scoped rifle. Practice regularly. Experiment with different loads and distances. With the right equipment, the right method, and a commitment to improvement, you’ll be achieving greater accuracy.
Remember that it is up to the user to ensure all work is done safely and to the best of their ability. Firearms can be dangerous if handled improperly.
Happy shooting.
