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.300 Blackout AR-15 Barrel Change

If you are exploring ways to enhance your AR-15, consider modifying it by switching to a .300 Blackout barrel. With this article, you’ll understand the process and key steps necessary to make this substantive change. Guided by Steve Ostrem from Brownells, Inc., you’ll learn about the requisite tools and the sequential instructions for safe barrel replacement.

The transition to a .300 Blackout barrel is transformative, offering a ballistic equivalence to the AK-47. It allows for the loading of heavy bullets at subsonic velocities, which is particularly useful for suppressors. One of the greatest benefits you’ll achieve is that the basic rifle bolt, magazine and other components remain unchanged. This article will illuminate the various aspects of this transformation, with specifics on the tools and materials needed as well as the installation process.

.300 Blackout AR-15 Barrel Change

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Table of Contents

Understanding the .300 Blackout AR-15 Barrel Change

As gun enthusiasts or professionals, you may understand the need for customizing your AR-15 to suit your specific uses. One such customization is the .300 Blackout barrel change.

The transformation of the AR-15 platform

The AR-15 is a powerful platform with high customization ability. One notable transformation is the conversion to the .300 Blackout cartridge. This adjustment offers enthusiasts an exciting twist on the traditional model by providing an alternative ammunition choice to the usual .223 or 5.56 mm rounds.

The function of the .300 Blackout cartridge

The .300 Blackout cartridge is a relatively new addition to the firearm industry. This cartridge has been designed to bring about the ballistic equivalent of the AK-47 into AR-15. It is also capable of shooting extremely heavy bullets at subsonic velocities. This function makes it especially useful for suppressor applications, which was one of the original purposes envisioned for this versatile round.

The compatibility of .223 or 5.56 AR with .300 Blackout by changing the barrel

Your AR-15, if using .223 or 5.56 mm rounds, is fully compatible with the .300 Blackout; the conversion can be done by merely changing the barrel. The original rifle bolt, magazine, and all components remain the same. The change primarily influences the choice of ammo you can utilize and can offer some unique advantages depending on your needs. This ease of conversion makes the .300 Blackout an enticing option for many gun owners.

Necessities for the Barrel Change

Performing a barrel change correctly and safely requires some specialized tools and a detailed understanding of the process.

Essential special tools for barrel installation

When about to change the barrel of your AR-15, certain special tools become essential for an effective installation. These tools are designed to aid you through each step and ensure a successful and safe barrel replacement.

Features of the Brownells BTech 300 Blackout carbine barrel

The Brownells BTech 300 Blackout carbine barrel that we will be employing for this process is 16 inches long, has a twist rate of one in eight, and has a set-up for a carbine length gas system. It also boasts a highly resilient black nitride coating, known for its smoother and longer-lasting finish.

Importance of good vise and its usage

A good vise is an integral part of your toolset when carrying out a barrel change. It should be securely mounted to a stable workbench and is essential for holding and stabilizing the upper receiver during barrel nut tightening or loosening. Its role cannot be overstated as it provides a solid and safe platform for you throughout the change process.

Usage of the Upper Receiver Action Block

Another tool indispensable for this process is the Upper Receiver Action Block. Made of synthetic material, it is designed to not mar or scratch your receiver. It aids in securing the receiver and allows for easy and safe handling during the barrel change.

Application of the Brownells AR-15 Armorer’s Wrench

The Brownells AR-15 Armorer’s Wrench is used for loosening and tightening the barrel nut. It also comes with wrench cutouts which fit the standard flash hider flats and some muzzle brakes. A square hole is also provided for a half-inch drive torque wrench if needed.

How Barrel Change Impacts Your AR

Executing a barrel change has a notable effect on your AR. Understanding these effects can aid you in making an informed decision.

The effects of changing the barrel

A change in your AR’s barrel impacts not only its functionality but also its overall performance and purpose. While retaining most components of the original rifle, the new barrel creates an entirely different experience.

Changes in the functionality of your AR after barrel change

The change in barrel allows your AR to fire .300 Blackout rounds, diversifying your ammunition options and bringing the power of an AK-47 into your AR-15. This change also significantly affects the range, accuracy, recoil, and noise levels of your rifle, each of which should be carefully considered before deciding to change your barrel.

Durability and longevity after the barrel change

While the durability and longevity of your AR primarily depend on the barrel’s quality, the change also provides an opportunity to enhance your AR’s overall performance. A high-quality barrel such as the Brownells BTech 300 Blackout has a nitride coating ensuring its longevity, offering a smoother, and thus longer-lasting finish.

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Step-by-Step Barrel Change Process

Barrel change may seem daunting, but with the right guidance, you can conduct it safely and effectively. Let’s go through the process step by step.

How to ensure the firearm is unloaded

Prior to starting the barrel change process, it is mandatory to ensure your firearm is unloaded. Check by removing the magazine, open the action and visually ensuring that the gun is empty. Only then should you proceed with the barrel change.

How to remove the magazine and separate the upper from the lower

After ensuring the firearm is unloaded, proceed on separating the rifle into its upper and lower parts. This can be achieved by pushing out both the takedown and pivot pin. Having done this, set the lower receiver aside.

The procedure of removing the bolt carrier group and the charging handle

Remove the bolt carrier group and the charging handle from the upper receiver. This is necessary to allow you to work on the barrel without these parts obstructing.

How to use the vise block to support and protect the receiver

Now, place the reinforcing insert, which comes with the Upper Receiver Action Block, inside the receiver. This will support and protect your receiver during the barrel change. Secure the upper receiver in the vise block, hold it shut firmly, and safe it in the vise. It is crucial for ensuring the receiver remains stable during the barrel change.

Dealing with Different Handguard Styles

Different models and makes of the AR-15 come with diverse styles of handguards. It’s indispensable to understand how these variations impact on the barrel-changing process.

How different handguard styles affect barrel change

The type of handguard on your AR is a key factor in its disassembly. With some handguards, you might need to remove them to access the barrel nut, while others may allow barrel changes without removal.

Removing the gas tube to turn the barrel nut

The gas tube must be removed to loosen the barrel nut. Do so by driving off the roll pin that holds it in place, back it out of the gas block and pull it out of the receiver.

The role of Armorer’s wrench in barrel change

The Armorer’s wrench comes into play at this point. Apply it to the barrel nut and turn it counterclockwise. Once loosened, remove the barrel nut which would allow you to ease the old barrel from the receiver.

Changing the Barrel Properly

Changing the barrel is at the core of the AR conversion process.

The technique of pulling out the old barrel

After the removal of the barrel nut, the old barrel should come out with relative ease. Make sure you handle the old barrel with care to avoid any damage.

Verifying the headspace of the new barrel

Before the new barrel goes in, it’s necessary to verify the headspace is correct. This step is crucial to ensure the safe operation of your AR after barrel replacement.

The alignment of the alignment pin in the receiver

When inserting the new 300 Blackout barrel, be alert to accurately align the barrel using the alignment pin into the cutout of the receiver threads.

The position and tightening of the barrel nut

With the barrel in place, spin the barrel nut on as far as you can manually. Then, with the Armorer’s wrench, tighten the nut clockwise until the next clearance for the gas tube is in alignment at the top center.

The importance of correct headspace

It is crucial to ensure the correct headspace on the new barrel. The right headspace will ensure safe and effective use of your AR after the barrel change.

Reinstalling the Gas Block and Gas Tube

With the barrel successfully installed and properly secured, it’s time to turn our attention to the gas block and gas tube.

Reinstallation of the gas block and gas tube

Following the barrel installation, reinstall the gas block and gas tube. These components are critical to the function of your AR rifle, so ensure they are securely inserted and positioned correctly.

Following Manufacturer’s instructions for correct installation

Many of these parts may require specific installation methods depending on their make and model. Make sure to follow the manufacturer’s instructions for the proper and safe installation of these.

Reusing or changing the original parts from the old barrel

When changing your barrel, you might decide to either reuse the original components from your old barrel or to replace them with new ones. Each option has its considerations and additional stages, and you should weigh these against your specific needs and preferences.

Precautions during the Barrel Change Process

The barrel change process, while largely straightforward, still requires precautions to ensure safety and effectiveness.

Safety precautions to follow during the barrel change process

Always confirm the firearm is unloaded before commencing any alterations. When handling tools and components, follow appropriate safety practices and use protective equipment where required. Always conduct barrel changes in a suitable workspace with a solid bench and appropriate lighting.

Understanding the risks and benefits associated with barrel change

Knowing and being ready for potential risks and challenges during a barrel change are an important part of the process. From the potential for damaging components to the risk of injury, stay proactive and reactive to manage these risks effectively.

Methods to minimize potential harm during the barrel change

Utilize necessary safety equipment, have an organized and clutter-free workspace, follow all safety guidelines and maintain focus throughout the entire procedure to minimize potential harm during the barrel change.

The Impact of Barrel Change on Your AR’s Performance

Changing the barrel of your AR can lead to significant impacts on its performance.

Possible performance enhancements after barrel change

A barrel change can lead to various performance enhancements depending on the specific type of barrel used and evenly increase the overall versatility of your AR-15. With the new .300 Blackout barrel, your AR-15 is capable of firing heavier, subsonic rounds, opening up additional uses for your rifle.

Determining the success of barrel change

The success of the barrel change is primarily measured by the seamless operation of your AR and the specific improvements gained, based on the reasons you chose to alter the barrel in the first place.

Dealing with potential issues after barrel change

There could be potential issues after the barrel change, including accuracy shifts or increased recoil. If any issues arise, understanding their source is important, as some could be natural results of the barrel change while others might be indicative of something being amiss during the change process.


Final thoughts about .300 Blackout AR-15 barrel change

The process of changing your AR-15 barrel to the .300 Blackout can appear complex, but with the right tools and guidance, you can achieve it effectively. The switch offers newfound versatility and could better align with your ammunition preference, thereby enhancing your shooting experience.

Importance of understanding the barrel change process

While the AR-15 is highly customizable, understanding the particular process of each change is crucial for effective and safe customization. For the barrel change, having a grasp on the necessary tools, the step-by-step process, and safety precautions helps assure a successful barrel change.

How barrel change can improve your AR’s performance

The change to a .300 Blackout barrel can offer significant improvements to your AR’s performance, from extended range to the ability to fire more massive, subsonic rounds. This kind of customization ensures that your AR is suited uniquely to your personal preferences and uses.

Encourage readers to explore more about ARs and barrel changes

Don’t just stop at understanding the .300 Blackout AR-15 barrel change. Keep exploring, learning, and testing the limits of what you and your AR-15 can do. There is an immense expanse of knowledge and potential waiting for you yet. Enjoy the journey!

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