Understanding the Language of Precision: MOA and Ballistics
In the precision world of shooting, where accuracy is the ultimate goal, the equipment plays a crucial role. From the rifle to the ammunition, every component contributes to achieving the perfect shot. Among these essential components, the scope mount often gets overlooked, yet it is critical for precision and extended range performance. This article will dive deep into one specific type of scope mount: the twenty MOA scope mount. We’ll explore what it is, why it matters, and how it can significantly enhance your shooting capabilities.
The fundamental concept behind a scope mount is simple: it securely attaches your optical device, the scope, to your rifle. However, the subtle nuances of the mount, particularly the angle it imparts, dramatically impact the performance, especially at long distances.
Before we delve into the details of the twenty MOA scope mount, let’s first understand the language used in precision shooting: Minute of Angle, or MOA. MOA is a unit of angular measurement, and it is critical in understanding how your bullet interacts with the world and how your scope makes adjustments for it.
Imagine a circle, and now imagine you are standing at the center. Each degree of that circle represents a certain portion of the circle. An MOA is defined as one-sixtieth of a degree, or about 1.047 inches at 100 yards. For practical purposes, it is usually rounded to one inch per 100 yards. So, if your bullet impacts one inch away from your target at 100 yards, you have a one MOA difference. At 200 yards, that same one MOA difference translates to two inches, and so on. It’s a practical way to measure the angular relationship between the shooter, the target, and the bullet’s flight.
The other crucial element to understand is ballistics – the science of how a bullet travels through the air. A bullet, once fired, is subject to the relentless pull of gravity, immediately pulling it towards the earth. The bullet doesn’t travel in a straight line; it follows a curved trajectory. This trajectory is influenced by several factors, including the bullet’s weight, its velocity, and the atmospheric conditions (wind, temperature, and air density).
The concept of bullet drop is key to understanding how a scope mount works. As the bullet travels further downrange, it will drop further down. The further you shoot, the more dramatic this drop becomes.
Wind also greatly influences the trajectory of a bullet. Even a gentle breeze can push a bullet off course, especially at longer ranges. The shooter must also account for this wind drift.
Unveiling the Angled Advantage: What is a Twenty MOA Scope Mount?
The twenty MOA scope mount is a specialized piece of equipment designed to compensate for bullet drop at extended ranges. Unlike a standard scope mount, a twenty MOA mount isn’t perfectly level. Instead, it incorporates a built-in downward slope, canting the scope downward relative to the rifle’s bore. The mount is angled downward so that the scope looks “down” a certain degree relative to where the barrel is pointing.
This built-in slope is precisely where the “twenty MOA” comes from. The mount provides an angle that will allow the scope to aim upwards. This upward aiming, when set up, will allow you to shoot at much longer distances. A 20 MOA mount tilts the scope downward by an angle equivalent to 20 minutes of angle.
Imagine the barrel of your rifle pointing straight ahead. With a standard scope mount, the scope would be parallel to the barrel. The bullet would drop because of gravity and other environmental conditions. A twenty MOA mount changes this equation. With the canted mount, the scope actually “looks up” slightly relative to the bore.
This offset is crucial. Without it, at longer distances, the scope would run out of elevation adjustment before you could reach the desired range because the reticle would have used up all of its elevation travel to compensate for the bullet drop. A 20 MOA mount gives the reticle a “head start,” allowing you to adjust your scope to account for the downward trajectory of your bullet over a longer distance.
How the Slope Works: Pre-Adjusting for Range
The twenty MOA scope mount works by pre-adjusting the scope’s elevation. This pre-adjustment is critical because the scope itself has a finite range of elevation adjustment. By canting the scope downward, the mount allows you to effectively shift the scope’s usable range. You’re essentially “borrowing” elevation from the scope itself.
When you mount your scope on a twenty MOA base, you are essentially using some of the scope’s internal elevation adjustment before you even begin to zero the rifle. This process allows the user more “travel” left on the scope for the user to dial up and reach longer distances. The pre-set is designed to provide more elevation travel without completely running out of adjustment.
This method gives the scope more adjustment, and the user can adjust for ranges that otherwise were unattainable.
Consider a scenario where your scope has 60 MOA of total elevation adjustment. If you mount your scope on a standard, zero MOA mount, you have access to the full 60 MOA range, but at long distances, the scope’s internal adjustments would need to compensate for bullet drop. Using a twenty MOA scope mount, you are using 20 of your scope’s available MOA right off the bat. Now, you’re left with 40 MOA to adjust, but the bullet drop at longer ranges can be reached by the use of the canted mount.
Real-World Benefits: Advantages in the Field
The twenty MOA scope mount offers several key advantages that can significantly enhance your shooting experience.
Extended Range Capabilities
The most significant benefit of a twenty MOA scope mount is its ability to increase the effective range of your rifle and scope system. Because the mount allows for additional elevation adjustments, you can reach distances that would be otherwise impossible with a standard mount. Shooters can use the mount to dial in for the longer distances and use the full amount of the scope’s adjustment for the maximum benefit.
Increased Elevation Adjustment
By tilting the scope, the twenty MOA mount helps to increase the usable elevation adjustment range. This effect is especially valuable when using a scope with a limited elevation adjustment range. This pre-set adjustment gives more range to achieve accurate shots at extended distances.
Simplified Shooting at Long Distances
With a twenty MOA mount, compensating for bullet drop at long distances is often simplified. You will dial your scope’s elevation to make adjustments.
Who Gains the Advantage: Users of the Twenty MOA Scope Mount
The twenty MOA scope mount is not for everyone. It is best suited for those seeking to extend the range or precision of their shooting abilities.
Long-Range Shooters
Long-range shooting is where the twenty MOA scope mount truly shines. Whether you are competing in benchrest shooting, participating in a long-range competition, or pursuing a long-range hunting, this type of mount gives you the ability to reach out further and with greater accuracy. These shooters understand the critical importance of precision and maximizing the scope’s adjustment range.
Competitive Shooters
Competitive shooting disciplines often involve targets at varying distances. A twenty MOA scope mount can give the competitive shooter a competitive advantage by allowing them to engage targets at longer ranges while still maintaining accuracy. Every tiny advantage can make a difference in competition, and this mount is one of them.
Hunters
The twenty MOA scope mount is a valuable tool for hunters. With this mount, hunters can ensure more accurate shots at longer ranges. The extra elevation can allow hunters to get the most benefit of their riflescopes.
Specialized Professionals
It is also seen in the hands of military and law enforcement professionals. Snipers and marksmen who need to ensure precision accuracy.
Finding the Right Fit: Choosing Your Mount
Selecting the right twenty MOA scope mount is critical to maximizing the performance of your shooting system. Here are several factors to consider:
Compatibility
Make sure your chosen mount is compatible with your rifle’s receiver and rail system. Most modern rifles use Picatinny or Weaver rails. The twenty MOA scope mount must properly secure to the rifle.
Scope Tube Diameter
Ensure that the mount rings match the diameter of your scope’s tube. Using the incorrect ring size can damage your scope and will certainly inhibit accuracy.
Height
The mount height is another important consideration. You’ll want to choose a height that allows you to comfortably maintain a proper cheek weld on the stock. The height will vary depending on your rifle, the scope size, and your preferences.
Material Quality
The material of the mount will dictate its durability and its overall lifespan. Quality mounts are typically made from either aluminum or steel. Steel is stronger but heavier; aluminum is lighter but less durable.
Brand Reputation
Choosing a reputable brand guarantees quality and reliability. Look for companies known for precision manufacturing and rigorous quality control.
Getting Started: Installation and Zeroing
Proper installation and zeroing are crucial steps to ensure your twenty MOA scope mount performs correctly.
Installation
Carefully follow the manufacturer’s instructions for mounting your scope. Typically, the process involves attaching the mount to your rifle’s rail, ensuring it is properly secured. Then, carefully set your scope in the rings, making sure to tighten the rings evenly and avoiding over-tightening.
Zeroing
Once your scope is mounted, you must zero it to your rifle. Zeroing is the process of adjusting the scope so that your point of aim corresponds to your point of impact. You will first want to make sure to bore sight your scope to a target at a given distance. Make any necessary adjustments to get the bullet to consistently strike the target.
Things to Consider
Zeroing with a twenty MOA mount may require you to adjust the scope’s elevation significantly at the start.
Limitations and Considerations
While the twenty MOA scope mount offers numerous benefits, it is not without its potential drawbacks.
Shorter Ranges
With a twenty MOA mount, you may experience the scope’s reticle to be high in the sight picture at shorter distances, leading to a less-than-ideal sight picture.
Zeroing Difficulties
Depending on your scope and rifle setup, you may encounter some difficulty in zeroing at shorter ranges.
Overall Adjustment
Some scopes may not have enough elevation adjustment to take advantage of the 20 MOA mount.
It is important to carefully consider your shooting needs, your scope specifications, and your desired ranges before deciding if a twenty MOA scope mount is right for you.
In Conclusion
The twenty MOA scope mount is a highly effective tool in the world of precision shooting, offering distinct advantages, especially for long-range applications. By incorporating a built-in downward slope, it extends the range of your scope and increases your available elevation adjustments. It’s essential for long-range hunters, competitive shooters, and any marksman seeking to extend their effective range.
Carefully evaluate your shooting needs, understand the mechanics of a twenty MOA mount, and select a high-quality mount from a reputable manufacturer.
By using the right mount, you can take advantage of your rifle and scope, and it can help improve accuracy. Take the time to find the correct setup and start achieving more accurate shots at extended distances.
