Buying an 80% Lower Receiver to Build an AR-15

In firearm terminology, a receiver refers to the part of the weapon that constitutes the frame or body. As far as the law is concerned, the receiver is actually what is defined as the actual weapon itself, and it is the part of the firearm that is subject to regulation and control. An 80% receiver refers to a receiver that is incomplete. Since they are not functioning firearms, 80% receivers are often not subject to the same regulations and controls that fully functioning firearms are.

Accordingly, it is possible, depending on local laws, to buy, sell or otherwise transfer the ownership of 80% receivers without the legal constraints that would otherwise affect the transfer. For guns like the AR-15, which are often subject to heightened controls, 80% receivers provide the market with an inventive way to trade. However, given the nature of AR-15 80% lower receivers, it is necessary to assemble the lower receiver into a functional piece to create a fully operational firearm.

Legal Status of 80% Receivers

Unlike with fully functional firearms, 80% lower receivers for AR-15s do not require a Federal Firearms License, or FFL, to trade. As such, it is possible to buy and sell 80% receivers without an FFL. Since it requires specialized tools, knowledge and skill to complete an 80% lower receiver into a full functional AR-15, the ATF does not consider it to be a firearm.

However, local, state and federal laws concerning the manufacturing and possession of firearms still apply. While there are differences throughout the United States depending on jurisdiction, the general rule is that if it is legal for you to possess an AR-15, it is legal to possess and ultimately complete an 80% lower receiver for an AR-15. In most places, it only falls under the law as a firearm once it is assembled into a 100% receiver.

Assembling an 80% Receiver

It is necessary to complete a variety of tasks using various tools to assemble an 80% lower receiver for an AR-15. To succeed, most people require some knowledge and experience of using these tools and working with metal. While there are many different variants, most require such tasks as drilling holes, removing material in the area of the fire control group, and coating if so desired. Commonly needed tools include drill presses and manual mills. Additionally, it is necessary to build the gun around the receiver once the receiver is complete. However, many consider the AR-15 to be one of the easiest to assemble in this way.

Advantages of 80% Receivers for Consumers

One of the biggest advantages to buying an 80% lower receiver for an AR-15 is that it does not require that the holder of an FFL be part of the transaction, and gun consumers are able to purchase the 80% receiver without restriction. While this method of acquiring an AR-15 requires some work, many owners who finished their guns in this way feel a special kind of pride from building their own firearm. As long as it legal for you to possess the actual firearm, it is legal for you to manufacture the gun for personal use, which gives you the freedom to choose the process of how you acquire your firearm.

If you are considering gun ownership, an 80% receiver represents an interesting, nonstandard, but often legal way of acquiring an AR-15. This method is especially attractive if you have a do-it-yourself attitude and the gumption to take on the task of craftsmanship on your own.

AR-15 Stock Options: Mil-spec vs Commercial Buffer Tubes

Most AR-15 owners know what the buffer spring is and what it does - it helps absorb the kick created by a round firing and forcing the bolt carrier group back and loading another round. Whether you are in combat, hunting, or target shooting you will want to be familiar with the type of buffer tube on your AR-15. This can prove especially helpful if you are looking for a new stock as it will be necessary to match it to the corresponding buffer tube. While they are similar in function, there are some differences between the mil-spec and commercial buffer tubes that you should understand in order to make an informed decision.

Reason For Variation

There is a simple reason for the variation of buffer tubes. The mil-spec variation is more expensive to manufacture, so the commercial buffer tube is available for those who want a cheaper alternative. While similar in appearance, there are a few subtle differences that dictate the type of stock necessary for your weapon.

Mil-Spec Manufacturing Process

The mil-spec is unique in that the threads located at the front are larger than the diameter of the actual tube. To make the product, the threads are lathed with the use of a large tube. When complete, the rest of the tube is reduced down to the appropriate diameter. Due to this intricacy, it takes longer and costs more to purchase mil-spec buffer tubes.

Commercial Manufacturing Process

The commercial manufacturing process is more direct in that it begins by using a tube that matches the diameter of the final tube. Just as any thread, the commercial tube is then lathed into the front end. This process takes far less time than the mil-spec alternative, making the final product far less expensive.

Summing Up The Differences

When observing the commercial tube and mil-spec tube side by side, the differences can be hard to pinpoint, and that is because they may be slight and difficult to observe. However, just a small variation in diameter makes for an entire different experience when it comes to firing the weapon. The primary physical differences between the two types of buffers are:

• Product diameter
• Thread diameter to tube diameter ratio

It used to be that the main cosmetic differences were the number of adjustment holes for the stock as well as commercial tubes being slightly slanted at the end. The end of a mil-spec buffer tube is flat and many manufacturers of commercial tubes have gone in that direction to make them look similar. While you can buy a new buffer assembly if you want to switch from one to the other, it can be expensive when you combine that with a new stock.