Mil-Spec vs Commercial Buffer Tubes: Which Is Better?

| Last Updated: May 11, 2021

The debate between the choice of a commercial buffer tube and a Mil-Spec buffer tube has been ongoing for many decades.

Certain people strongly believe in the Mil-Spec buffer tubes due to their practicality as well as customization abilities.

In contrast, others are set on the commercial buffer stock due to its straightforwardness and low price. 

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Mil-Spec vs Commercial Buffer Tubes

Mil-Spec Buffer Tube

Commercial Buffer Tube

Pros

Pros

Accessories

Affordable

Durability and strength

Larger tube diameter

Better stock upgrades available

Standardization for civilian weapons

Cons

Cons

Price

Less quality than mil=spec

Best For

Best For

Military and law enforcement

Civilian rifle users, competitive shooters, and gun owners.

What Defines a Mil-Spec Buffer Tube?

A Mil-Spec buffer tube is also more commonly known as a receiver extension, sticking out the chosen rifle. The name of the buffer tube was derived from the spring located within the tube, also known as an action spring, while the part that is more heavily weighted is usually referred to as the buffer recoiler. 

It is usually made of a metal alloy that serves two very distinct functions. First, it controls the recoil to return the bolt back to its starting position. Secondly, the Mil-Spec buffer tube is the point at which the buttstock usually is attached to the chosen rifle. 

Mil-Spec buffer tubes are noticeable in their differences with commercial buffer tubes when it comes to the diameter, with Mil-Spec often being on the smaller side (1.14”). Commercial buffer tubes and Mil-Spec buffer tubes are very similar in their designs. 

However, Mil-Spec Tubes are more widely available,  as well as being much more customizable as well as compatible. Furthermore, Mil-Spec buffer tubes allow for increased opportunities when it comes, further attachments as well as buttstocks. 

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What Defines a Commercial Buffer Tube?

It is important to note that the only major or notable difference between a Mil-Spec buffer tube and a commercial buffer tube is the external barrel or stock end’s diameter. The diameter of the specific rifle in question will be the decisive factor in choosing between the two differing buffer tubes. 

Commercial buffer tubes are usually around 1.17” in diameter when measured from the outside, while on the receiver side, it is usually about 1.17” in diameter. Commercial buffer tubes are more commonly produced since they are usually cheaper; owing to the more standardized measurements as well as the type of metals they are forged from. 

Additionally, the main selling point for a commercial buffer tube is that of the low cost, with commercial specifications, which are an addition to the tube that is already protruding. 

The lower quality of metal used (7075-T6 alloy) is welded onto the cap of the rifle butt, making the buttstock gain in length and creating an additional slant. 

The separating factor for most gun owners is that of price versus the quality of the metal. 

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Relevant Characteristics Between Mil-Spec and Commercial Buffer Tube

The characteristics that separate the Mil-Spec buffer tube and the commercial buffer tube are minor in practice but have far greater implications in terms of future usage of the tube as well as further attachments. 

The Commercial buffer tube is marginally bigger, while the Mil-Spec buffer tube is normally slightly smaller, although allowing for further attachments or customizations to be made.

Mil-Spec Buffer Tube

Characteristics

Commercial Buffer Tube

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Enter your text here...

7075-T6 Alloy

Materials

7077-T7 Alloy

1.148”

Diameter

1.168”

1-3 UN thread

Threads

16-16 UN thread

$300

Cost

$250

How to Tell the Difference Between a Mil-Spec and Commercial Buffer Tube?

For a greater understanding, the differences and similarities between a Mil-Spec buffer tube and a commercial buffer tube will be presented. Although both tubes serve a similar purpose and are often very similar in their designs, the differences between the two are quite evident.

Mill-Spec and Commercial Buffer Tube Differences

First, a stark difference is in the materials that they use. Usually, Mil-Spec tubes are made up of a superior metal, which is usually the 7075-T6 alloy. 

This metal is of higher quality in terms of its makeup and practicality as it is far more durable, rugged, and long-lasting in terms of metals used for rifles. Additionally, the Mil-Spec buffer tube’s diameter is usually smaller than that of the commercial buffer tube and customers normally attach additional upgrades onto it later. 

The commercial buffer tube is a set size, as it’s a more generalized and cheaper option for customers who exclusively want a buffer tube and no additional upgrades. Furthermore, the thread that is used is also different as the buffer tubes are often used for different purposes. 

Photo credit: windhamweaponry.com

The Mil-Spec is usually threaded with 1-3 UN thread, while commercial buffer tubes are always threaded with 16-16 UN thread. The differences between these two threads are important. 

Another notable difference is that of the price, with the commercial buffer tube always being cheaper as it is standardized and the production of the tube is more streamlined. The Mil-Spec buffer tube is normally on the more expensive side as it is.

Mil-Spec buffer tubes remain the more popular option generally in the rifle owners’ community.

Mill-Spec and Commercial Buffer Tube Similarities

Mil-Spec and commercial buffer tubes have a lot of similarities between them, with most average people not being able to tell the difference immediately. While it is known that the alloy used in Mil-Spec buffer tubes is often of superior quality, the alloy used in commercial buffer tubes is usually almost identical. 

Long-term usage will allow for the differences in the quality to become more obvious, but for practical usage of a rifle, the similarities between the metals are significant. Furthermore, the price difference between the two is noticeable, while not being extravagantly different.

Commercial buffer tubes are still cheaper, while Mil-Spec buffer tubes are more widely produced, customized, and accessible. 

Furthermore, both buffer tubes are forged in metal threads, meaning they are forged and then rolled piece by piece. While the differences are found in the lengths of the rolled thread, the similarities are far more obvious, with there only being a fraction of an inch difference between the two.

Both the commercial buffer tube and the Mil-Spec buffer tube are utilized as a receiver extension and are usually added to AR-15 and other semi-automatic rifles.

The buffer tubes are also both put into practice in the form of a basic mounting point for a cylindrical pistol or buttstock and as such have made the addition of either very popular throughout the rifle community.

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Advantages of Mil-Spec Buffer Tubes

The Mil-Spec buffer tube offers many advantages, both by itself, and when in comparison to commercial buffer tubes. 

A major selling point for Mil-Spec buffer tubes is that of the options available to the customer when it comes to stock upgrades in an aftermarket manner. 

Rifle owners are known for often wanting increased customization in terms of buttstocks, aftermarket upgrades as well as additional attachments. Mil-Spec buffer tubes are known for being very advantageous in this area, making it the most popular choice between the two in general. 

Mil-Spec configurations are also more widely available for the most popular rifles such as the AR-15, leading to both sellers and buyers making use of it more often. 

Throughout the rifle-owning community, it is accepted that the Mil-Spec buffer tube is the industry standard, making it much more accessible and widely available when compared to its commercial counterparts. 

Furthermore, the accessories are often sold along with the Mil-Spec buffer tube such as sling attachments, buttstocks as well as buffers. The compatibility of Mil-Spec buffer tubes, in terms of future add-one, is the most significant advantage when being compared to a commercial buffer tube. 

The quality of the materials that are used within the alloy is another main advantage of the Mil-Spec buffer as a whole, making it the most popular buffer attachment throughout the rifle community. 

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In summary; the quality of the materials used, how they can be attached and customized is what makes the Mil-Spec buffer tube the most advantageous. 

It is also known that unfortunately, Mil-Spec buffer tubes cannot be fit to a commercial buffer tube, while it is also the same when the roles are reversed.

Brands That Use Mil-Spec Buffer Tubes

Mil-Spec buffer tubes are used by most leading gun manufacturers throughout the world, although specifically in the United States. The most well-known companies that have implemented these buffer tubes and all their accessories are; Stag, Lmt as well as Colt. 

These are famous gun manufacturers and have been leading the way within the industry for many decades already. Other gun manufacturers also use the Mil-Spec buffer tube, while the aforementioned gun manufacturers are the most well known as well as producing by far the most buffer tubes throughout the last few decades. 

Advantages of Commercial Buffer Tubes

Commercial buffer tubes are, in their own way, advantageous when being compared to the more popular Mil-Spec buffer tube. The first and main advantage, that people end up choosing, is that they’re slightly larger

Furthermore, the price of the commercial buffer tubes is often much cheaper when being compared to any Mil-Spec buffer tubes. The main reason why commercial buffer tubes are so much cheaper is down to the manufacturing processes, with some commercial companies selecting to lathe the tube instead of forging it out of rolls of alloy metals. 

Photo credit: sigtalk.com

Most commercial buffer tubes are produced in a standardized manner, cut straight from a material that is derived from a raw block of metal. Another advantage of commercial buffer stock is that of having a set standard, in terms of diameter, thread, and price which cannot be said for Mil-Spec buffer tubes. 

The setup, production, and uses of the commercial buffer tubes are less when being compared to Mil-Spec buffer tubes as the amount of customization and accessories that can be added are significantly reduced. 

While there are many advantages of a commercial buffer tube, it is still not as desirable for the average consumer when compared to the Mil-Spec one, meaning that the best opportunity for commercial buffer tubes comes from the price reduction, standardization as well as the known elements of the quality. 

In summary, the commercial buffer tubes have their place within the rifle-owning community. While it cannot be compared to the Mil-Spec buffer tube in terms of customization, after-market accessories as well as the quality of the alloys, it has a few advantages of its own. 

The main advantage is the price, as it is much cheaper, usually, when compared to Mil-Spec buffer tubes. Additionally, it is standardized, making it easier for customers to know what they're getting as well as being more reliable in terms of reputation. 

Bottom Line

The bottom line is that; although the commercial buffer tube and the Mil-Spec tube are very similar in appearance and application, they are usually utilized for very different things. Commercial buffer tubes are mostly chosen for their price, standardization as well as general applications. 

On the other hand, Mil-Spec buffer tubes are utilized for their wide range of uses, the ability for the tube to be customized as well as the tube being able to be implemented in the form of aftermarket accessories. 

The Mil-Spec, in general, seems to be the most desirable option, when taking everything into account and is by far the most popular option, especially since it is the general industry-standard accepted tube in terms of accessibility and customization on the most popular rifle throughout the entire United States; the AR-15.

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People Also Ask

Below are some common questions surrounding this topic.

Does the Buffer Tube Length Matter?

The buffer tube length does not usually make a difference in terms of application, although many rifle owners seem to favor the shorter length Mil-Spec form for accessories and aftermarket parts. While the commercial buffer length is slightly more, making it more desirable for competitive shooting. 

Can You Change a Commercial Buffer Tube to a Mil-Spec Tube?

Unfortunately, the commercial and Mil-Spec buffer tubes cannot be changed or swapped around since they are not the same size in diameter or thread length. 

Can You Put a Mil-Spec Upper on a Commercial Lower?

You cannot put a Mil-Spec Upper on a commercial lower since the diameter sizes of the two tubes are slightly different. While the difference is not noticeable with the naked eye, in practice, it is impractical or impossible and a decisive choice should be initially made. 

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Can You Put a Mil-Spec Stock on a Commercial Buffer Tube?

You cannot put a Mil-Spec stock on a commercial buffer tube since the sizes of the known diameter are different in length. While the difference in thread size and diameter size is almost negligible, it is still impractical and will not effectively work. 

Can You Use a Standard Buffer Tube on an AR Pistol?

You can use a standard buffer tube on an AR Pistol, the attachment can enhance the pistol just as it would enhance a more powerful rifle. Many gun users prefer this option as it increases and adds to the accuracy and usefulness of the rifle.



Josh Lewis the managing editor at Gun Mann and when he isn't writing about guns he is more than likely tinkering with them. He also enjoys hunting, fishing and spending time outdoors. As a lifelong gun owner he knows his stuff!