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Tech Tip: Mil-Spec vs. Commercial Buffer Tubes

In this detailed guide entitled “Tech Tip: Mil-Spec vs. Commercial Buffer Tubes,” Brownells Inc. offers in-depth analysis on the complex world of lower receiver extensions, also known as buffer tubes. Whether you’re looking to build an AR from scratch or seeking to improve an existing AR, understanding these variations can aid in deciding the appropriate buffer tube for your needs.

This comprehensive guide provides observations regarding the distinct differences between mil-spec and commercial buffer tubes, largely focusing on the outside diameter. It is packed with crucial information, from measurement methods to highlighting the fabrication process. The guide’s goal is to equip you with the understanding necessary to confidently choose between a Mil-spec or commercial stock. The satisfaction guarantee offered by Brownells Inc. underscores their commitment to your overall experience.

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Understanding Buffer Tubes

Definition of a Buffer Tube

A buffer tube, also known as a lower receiver extension, is an essential component found in firearms, particularly within AR-15 or M-16 style rifles. In these firearms, the buffer tube acts as a housing for the buffer and recoil spring. These tubes have a threaded end which screws into the firearm’s lower receiver for a secure attachment.

Role and Importance of Buffer Tubes in Firearms

Buffer tubes play a significant role in firearms. They absorb the recoil generated by the firearm when it is fired, allowing for a smoother user experience. Without buffer tubes, the firearm would be less controllable and the recoil more forceful, which could lead to inaccuracies during firing. Moreover, they serve as a point of attachment for the rifle’s buttstock, making it an essential component for firearm assembly.

The Basics: Mil-Spec vs. Commercial Tubes

Key differences between Mil-Spec and Commercial Tubes

The primary distinguishing factor between military specification (Mil-Spec) buffer tubes and commercial buffer tubes is their outside diameter. Mil-Spec tubes typically have a diameter of 1.145 inches, while commercial tubes have a slightly larger diameter. Additionally, there are differences in the manufacturing process, where Mil-Spec tubes are produced from billet aluminum, while commercial tubes use an extrusion process.

General Considerations when Choosing between Mil-Spec and Commercial Tubes

When considering between Mil-Spec and commercial tubes, keep in mind that your choice should align with your specific needs and preferences. Evaluate the type of rifle you have or are planning to build, the buttstock you intend to use, as well as your budget. Moreover, remember that consistency matters. If you opt for a Mil-Spec buffer tube, ensure the buttstock you select is also Mil-Spec.

Examining Mil-Spec Buffer Tubes

Understanding the Construction of Mil-Spec Tubes

Mil-Spec buffer tubes are made from billet aluminum. This manufacturing process allows for thinner walls, resulting in a buffer tube that maintains rigidity, but with a reduced weight. It is important to note that this process generally results in a higher quality product, hence Mil-Spec tubes are typically more expensive than their commercial counterparts.

Benefits of Using Mil-Spec Tubes

There are several advantages to using Mil-Spec tubes. Their smaller diameter and lighter weight contribute to a more compact and lighter firearm, an attribute desired by many firearm enthusiasts. Furthermore, they are widely regarded as being more durable and higher quality due to the manufacturing process involved.

Potential Drawbacks of Mil-Spec Tubes

Despite their advantages, potential drawbacks to consider when using Mil-Spec tubes include their higher price compared to commercial tubes. They may also be less readily available due to their specific production process.

Tech Tip: Mil-Spec vs. Commercial Buffer Tubes

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Exploring Commercial Buffer Tubes

Comprehending the Design of Commercial Tubes

Unlike Mil-Spec tubes, commercial buffer tubes are made from an extrusion process, which results in a buffer tube with a larger diameter. This method is more cost-effective, enabling these buffer tubes to be priced more affordably.

Advantages of Using Commercial Tubes

Commercial tubes offer a cost-effective alternative without major performance compromises. With their larger diameter, commercial buffer tubes offer a more expansive space for heavier and larger buffer systems, which may be ideal for users looking to shoot heavier calibre rounds.

Possible Disadvantages of Commercial Tubes

Albeit cost-effective, the main disadvantage to using commercial buffer tubes lies in their compatibility. Due to their larger diameter, commercial tubes may not be compatible with Mil-Spec stocks, limiting customization options.

Measuring the Outside Diameter of Buffers Tubes

Importance of Measuring the Outside Diameter

It is crucial to measure the outside diameter of your buffer tube accurately. This is to ensure that your chosen buffer tube is compatible with your selected buttstock, thus avoiding any potential issues during firearm assembly.

Step by Step Guide on How to Measure the Diameter

Start by sliding the buttstock back to expose the tube, then use a set of calipers to measure the diameter. Ensure to measure a few times to verify the reading for accuracy. Remember, a Mil-Spec buffer tube will have a diameter of 1.145 inches, while the diameter for a commercial tube will be slightly larger.

Influence of the Manufacturing Process on the Tube

Comparing the Manufacturing Process of Mil-Spec and Commercial Tubes

The manufacturing process is a pivotal factor that determines many of a buffer tube’s characteristics. Mil-Spec tubes, made from billet aluminum, result in a lightweight yet sturdy tube. Conversely, commercial tubes made from an extrusion allows for cost-efficient production but results in a larger diameter.

Why Commercial Tubes have a Larger Diameter

The larger diameter of commercial tubes arises from their manufacturing process. The extrusion process often requires a more considerable volume of material, hence, resulting in a larger diameter compared to Mil-Spec tubes.

Buffer Tubes Compatibility

Understanding Buffer Tubes Compatibility with Carbine Springs and Buffers

Regardless of the type—Mil-Spec or commercial—buffer tubes can accommodate any carbine spring or buffer. This flexibility allows for an array of carbine springs and buffers to be compatible with both types of tubes.

Insight on Buffer Tubes Compatibility with AR-15 or M-16 lower

For AR-15 or M-16 rifles, either a Mil-Spec or commercial buffer tube will suffice as they are designed to be compatible with these firearms’ lowers. Simply ensure that the threads match correctly during installation.

How to Determine the Type of Buffer Tube to Purchase

Factors to Consider when Buying a Buffer Tube

Multiple factors come into play when selecting a buffer tube. First, consider the rifle and buttstock type you intend to use, ensuring their compatibility. Second, assess your budget. Lastly, take into account your preference in terms of weight and diameter.

Advice on Stock Upgrade

If you plan on upgrading your stock, carefully examine your existing setup. Remember, commercial stocks will not fit on Mil-Spec tubes and vice versa. Therefore, ensure that any upgrade aligns with your current buffer tube specifications.

Purchasing Buffer Tubes and Butt-stocks

Overview of the Buying Process

Before buying, familiarize yourself with the key differences between Mil-Spec and commercial tubes. Substantially, have a clear understanding of what your firearm requires in terms of compatibility and performance. Be sure to purchase your tube or buttstock from a reputable vendor to ensure quality.

How to Order or Find Information on Lower Receiver Extension Tubes and Butt-stocks

Information on lower receiver extension tubes or buttstocks is easily accessible from various online platforms, including manufacturers’ websites or firearm enthusiast blogs. To order, browse through these platforms, select your preferred product, and follow the provided steps to finalize your purchase.


Recap on the Differences between Mil-Spec and Commercial Buffer Tubes

The chief distinction between Milspec and commercial buffer tubes lies mainly in their outside diameter, and the manufacturing process employed. Mil-Spec tubes are lighter, durable and more expensive, while commercial tubes are more cost-friendly with a larger diameter.

Why the Choice of Buffer Tube is Critical

The choice of a buffer tube in any firearm assembly is critical. The buffer tube not only houses your rifle’s spring and buffer, improving your firearm’s functionality, but also plays a key role in attaching the buttstock. Therefore, making an informed decision is imperative to ensure compatibility, durability, and daily performance.

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