Understanding AR-10 Scopes
Choosing the right scope for your AR-10 goes beyond simply picking one off the shelf. It’s about understanding the relationship between your rifle, the intended application, and the optical features that will optimize your performance. The .308 Winchester, with its impressive ballistics, demands a scope that can keep up with its range and accuracy.
What to Look For in an AR-10 Scope
Objective Lens Size
The objective lens, the lens at the front of the scope, plays a pivotal role in light gathering. A larger objective lens diameter allows more light to enter the scope, resulting in a brighter and clearer image, particularly in low-light conditions such as dawn or dusk. However, a larger objective lens often means a heavier and bulkier scope, and may necessitate taller scope rings, impacting cheek weld. The size should be carefully considered based on the intended use case. While a larger lens is often better for hunting, for tactical applications where quick target acquisition is key, it could present a trade-off.
Magnification Range
The magnification range defines how much closer the target appears. Scopes with variable magnification are versatile, allowing you to adjust the power for different distances and shooting scenarios. For close-range engagements, lower magnification (e.g., 1x-4x) is ideal. Higher magnifications (e.g., 4x-16x or even higher) are better suited for long-range target shooting or hunting at distance. The right magnification hinges entirely on your typical shooting ranges.
Reticle Type
The reticle, the aiming point within the scope, is crucial for target acquisition and accurate shot placement. Reticles come in a variety of designs, each with its advantages.
BDC (Bullet Drop Compensation) Reticles: These reticles are calibrated for specific ammunition and distances, providing holdover points to compensate for bullet drop at various ranges. They are user-friendly and quick to employ in the field, but their accuracy is reliant on using the correct ammunition.
Mil-Dot Reticles: These reticles utilize mils (milliradians) for range estimation and holdover calculations. They are highly versatile, favored by many long-range shooters. They provide more precise holdover and windage adjustments.
Illuminated Reticles: These reticles have a light-up feature, often in red or green, which significantly improves visibility in low-light conditions or against dark backgrounds.
The best reticle for you depends on your shooting style and the types of targets you engage.
Adjustment Turrets
Adjustment turrets allow you to fine-tune the scope’s zero and make adjustments for windage and elevation. The two primary adjustment systems are MOA (Minute of Angle) and MIL (Milliradian).
MOA: One MOA corresponds to approximately 1 inch at 100 yards. MOA adjustments are common and familiar to many shooters.
MIL: One MIL corresponds to 10 centimeters at 100 meters. MIL adjustments are popular in military and law enforcement circles due to their mathematical simplicity.
Durability and Build Quality
The AR-10 generates significant recoil. A scope must withstand the forces to maintain zero and function reliably. Look for scopes built with high-quality materials (aircraft-grade aluminum, etc.), and consider features such as being sealed and purged with inert gas (like nitrogen or argon) to prevent fogging and ensure waterproofness.
Eye Relief and Eye Box
Eye relief is the distance from the ocular lens (eyepiece) to your eye that allows for a full field of view. Insufficient eye relief can lead to injury from recoil. A generous eye box (the area in which the eye can move while maintaining a full field of view) makes it easier to acquire the target quickly, and less demanding of precise eye positioning. Both factors play crucial roles in shooting comfort and speed.
First Focal Plane (FFP) vs. Second Focal Plane (SFP)
The placement of the reticle within the scope dictates the focal plane.
FFP (First Focal Plane): The reticle size changes proportionally with magnification. The holdover points and range-finding scales remain accurate at all magnification levels.
SFP (Second Focal Plane): The reticle size remains constant regardless of the magnification. Holdover points are only accurate at the highest magnification. The SFP is often found in scopes designed for hunting because of a simpler, less cluttered reticle.
Considerations for AR-10 Rifles
Recoil
The potent .308 Winchester cartridge generates substantial recoil. It’s critical to select a scope built to endure these forces. This means robust internal components, a shock-resistant design, and a reliable construction. A scope that fails to withstand the recoil will not hold zero, rendering it useless.
Shooting Distance
The .308 Winchester is capable of accurate shots at long ranges, but to use this capability, your scope needs to be up to the challenge. Consider a scope with a wide magnification range (e.g., 3-15x or even higher) if you often shoot beyond 300 yards. The reticle design should support the ability to compensate for bullet drop at extended distances.
Intended Use
The intended use case dictates the best scope features. For hunting, prioritize low-light performance, rugged construction, and perhaps a quick-acquisition reticle. For target shooting, precision is paramount; choose a scope with fine adjustments and a detailed reticle. Tactical applications might require a scope that is fast on target, durable, and optimized for shorter-to-medium ranges.
Top Scope Recommendations
The “best” scope is subjective and highly dependent on your individual needs and budget. However, based on various factors, here are some scope options designed to provide outstanding performance on an AR-10.
A High-Performance Optic
Consider a model by a reputable manufacturer known for clarity and durability. These scopes usually offer a wide magnification range (e.g., 3-18x or even greater), a well-designed, illuminated reticle (such as a MIL-based reticle for long-range work), and precise, repeatable adjustment turrets. Features like first focal plane, exceptional light transmission, and robust construction are non-negotiable. Though pricier, the investment pays off in reliability, versatility, and shooting enjoyment. This scope might have a premium price tag, but offers everything a discerning shooter could need.
A Budget-Friendly Choice
There are numerous scopes that combine good value and performance, making them an excellent option for budget-conscious shooters. Focus on build quality, clarity, and a reliable reticle. Look for scopes that are waterproof and fog-proof to ensure reliable performance in different conditions. While you might sacrifice some high-end features like super-premium glass, the trade-off can be worthwhile if the scope meets your requirements.
A Scope for Long-Range Shooting
If you are serious about stretching the AR-10’s legs, seek a scope that specializes in long-distance work. This includes a high magnification range (4-20x, or even more), a highly accurate reticle (such as a Christmas tree style reticle), and easy-to-use, precise adjustment turrets. FFP designs excel in these scenarios. The scope should be designed to manage the conditions often encountered at long-range – strong winds, atmospheric changes, and extreme distances.
A Scope for Hunting
A hunting scope should prioritize features like excellent light transmission, ruggedness, and a reticle designed for fast target acquisition. A good balance between magnification and objective lens size is important. Waterproofing is essential. A scope with a BDC reticle, or a similar design, can make it easy to compensate for bullet drop at varying ranges. A smaller and lighter weight scope helps for those who prefer to carry their AR-10 on their hunt.
A Scope for Tactical Use and Home Defense
For tactical applications or home defense, speed and reliability are paramount. Consider a low-power variable optic (LPVO) with a magnification range of 1-4x or 1-6x. A bright, illuminated reticle, such as a red dot or circle-dot, enhances rapid target acquisition. Durability, shock resistance, and a simplified reticle are key. A lightweight design will make your AR-10 more maneuverable in close quarters.
Key Features to Consider When Choosing an AR-10 Scope
Magnification
Magnification dictates how closely you can see your target. The best magnification range for an AR-10 depends on your primary use case. 1-4x or 1-6x is generally sufficient for close- to mid-range engagements. 3-9x or 4-16x is suitable for general-purpose use, and higher magnifications (e.g., 5-25x or more) are ideal for long-range shooting.
Reticle
The reticle is the aiming mechanism. The correct selection depends on your shooting style, the distance you shoot, and the targets you engage. BDC reticles are fast and easy to use. Mil-Dot and similar ranging reticles are preferred by serious long-range shooters. Illuminated reticles provide better visibility in low light conditions.
Objective Lens Size
A larger objective lens gathers more light, which is beneficial in low-light situations. However, it can increase the scope’s weight and bulk. Choose the size that balances light-gathering with overall size and weight. A compromise between lens size and portability is usually recommended.
Adjustment Turrets
Turrets enable precise adjustments for windage and elevation. Choose MOA or MIL adjustments based on your preference and the reticle design. Ensure the turrets are easy to adjust, repeatable, and offer clear markings. Zero resetting turrets allow for quick adjustments back to zero.
Durability and Construction
The AR-10 generates recoil. Ensure that the scope is built to withstand those forces and that it can maintain its zero. Look for scopes made from aircraft-grade aluminum or similar high-quality materials, that have sealed and purged with inert gas.
Mounting Options
Choose the right scope mount for your AR-10. Consider the height and the distance to the eye piece. Proper mounting is essential for accurate shooting and proper use.
Mounting and Zeroing Your AR-10 Scope
Mounting a scope involves attaching it to your AR-10’s receiver using the appropriate mount. Ensure the mount is properly torqued to prevent movement. After mounting, center the reticle by looking through the scope. Zeroing involves firing several shots at a target and adjusting the turrets to bring the point of impact to the point of aim. Repeat the process until your shots consistently hit the target at the desired range. Confirm the zero at the range you plan to frequently shoot. Always ensure the firearm is unloaded and pointed in a safe direction.
Maintenance and Care
Cleaning the scope’s lenses regularly with a soft, lint-free cloth keeps them clear and improves optical performance. Store the scope in a cool, dry place. Avoid exposing the scope to extreme temperatures or direct sunlight. Always protect the lenses from damage.
Conclusion
Choosing the best scope for your AR-10 is a crucial step in maximizing the rifle’s potential. The goal of the **best scopes for AR-10** rifles is to create synergy between the shooter, the rifle, and the optics. Considering the features, intended use, and your budget will lead you to an optic that enhances accuracy, range, and the overall shooting experience. Select a scope that aligns with your shooting goals and the demands of the .308 Winchester cartridge. By following these guidelines, you will make a more informed decision and be well-equipped for success.
FAQs
Many questions arise when selecting an AR-10 scope.
What is the best magnification for AR-10? This depends on your primary use. 1-6x are good all around. For long-range, you’ll need greater magnification.
How to choose the correct scope mount? Make sure to select a mount that matches your scope’s tube diameter and the rail system. A good starting point is to see what the manufacturer recommends.
What is the difference between First Focal Plane (FFP) and Second Focal Plane (SFP) scopes? The reticle’s appearance in an FFP scope changes with magnification, whereas an SFP reticle remains constant.
Why do I have trouble with my scope fogging? If your scope fogs up inside, it might not be sealed properly. Select a scope that is filled with a gas (like nitrogen) and sealed.
Is more expensive always better? Not necessarily, there are a lot of scopes that offer good quality and great value for the price. However, spending more usually gets you better optical clarity, higher-quality glass, more reliable adjustment turrets, and better overall durability.
