Barrels come in a lot of different shapes, sizes, and lengths. With the large part they play in any build both functionally and geometrically, they play a huge role in fitting the desired application of a rifle. Here, we will do our best to describe the different barrel lengths, profiles, and finishes that are available in the configurators found in our product pages. This article is comprised of knowledge derived from our own testing and experience and is by no means authoritative or all-encompassing, nor is it meant to be. Rather, this page exists to help you, the consumer, make an educated decision when configuring your upper with our Build Your Own Upper (BYOU) page. Since our primary barrel supplier is Ballistic Advantage®, any statements made here pertain to their line-up of barrels unless otherwise specified.


There are a lot of different combinations of barrel length, gas system length, gas port size, and barrel profiles. One of the largest elephants in the room when it comes to this topic from a civilian perspective is that 16.00" is the minimum length required for a firearm to be classified as a standard rifle, which does not have any additional Federal regulation or require additional tax duty and registration. Of course, various localities will vary in this regard, so that is up to you to do your due diligence to ensure that you remain in compliance with your local laws. That being said, 16" is the most common length for AR-15 pattern rifles, particularly for factory rifles, for the relative regulatory simplicity of their production and acquisition. With the BYOU system, you can obviously select shorter barrel lengths. In some cases, namely 13.9" and 14.5", these can be paired with a muzzle device that is permanently attached to achieve the minimum overall length of 16". For those on the shorter end of the spectrum, 10.3", 11.5", and 12.5", there are currently two legal options for their use: either configured with a pistol receiver or registered as a Short-Barreled Rifle (SBR). The barrels themselves are not regulated, but play a major role in determining the regulator status of the configuration of an existing firearm when they are used in conjunction. As with many things in the industry, these options are subject to change. As we stated before, it is up to you to discern the legalities and requirements of your locale for any firearm or component you order from us.

With that bit of legal background established, let's get into the meat and potatoes. Click any of the links below to see the details and our notes on each of the barrel lengths:

16.0" (Mid-Length)

Modern Series, Hanson, Premium Series, and Classic Series

14.5" (Mid-Length)

Modern Series, Hanson, and Premium Series

13.9" (Mid-Length)

Modern Series and Hanson

12.5/12.3" (Carbine)

Modern Series and Hanson

11.5/11.3" (Carbine)

Modern Series and Hanson

10.5/10.3" (Carbine)

Modern Series, Hanson, and Classic Series


You can find a wide variety of barrels on the market today. With that variety comes an equally wide range of quality. Though it is definitely not the sole indicator of quality, the material used in a barrel is the first hurdle to jump for determining the quality of a particular piece. There are two materials that are used for the barrels we offer, neither of which are the "mystery meat" of the cheaper barrels of unknown origin you can find out there. Both are high-quality and will last you quite some time, but offer distinct benefits and drawbacks depending on your desired application, so choose wisely. In most cases, Mil-Spec 4150 CMV is a safe bet, so our recommendation is to go that route if you are unsure.

4150 CroMoly Vanadium (CMV/CroMoV)

Modern Series and Hanson

416R Stainless Steel

Premium Series


For the mil-spec 4150CMV barrels, there are two different flavors available in our offerings: QPQ (Quench-Pour-Quench) Nitride and a traditional heavy phosphate-coated exterior with a hard chrome-lined interior bore and chamber. Continuing the trend of a lack of free lunches at this buffet of information, there are of course benefits and drawbacks to both. Since the value of 416R as a barrel material is in it's material qualities, they are simply bead-blasted to reduce glare and maintain those qualities.

QPQ Nitride

Modern Series and Hanson


Classic Series

0 Items