Probably the two main common sizes in AR uppers are 16 and 20 inch AR uppers. These offer unique benefits and confer distinct advantages to the operators of builds completed with them. Here’s a little more about what you should know about these upper sizes.
16 Inch AR Uppers
A 16 inch AR upper will yield a carbine. Thanks to its shorter barrel, a rifle made with a 16 inch upper will be lighter and more compact than one with a longer barrel.
Some operators argue that the shorter, more compact profile of a carbine-style AR gives it faster, superior handling to one made with a longer barrel.
They argue that these attributes make carbine-length rifles better in close-quarters engagements and therefore better for defensive applications.
Another thing to note about a 16 inch AR is that it will exhibit less barrel whip. This can result in a rifle that is more inherently accurate than one with a longer barrel.
At the same time, the sight radius of a 16 inch barrel is much shorter than that of a 20 inch barrel, which can make it more difficult to shoot the rifle accurately, despite the platform’s inherent capabilities.
20 Inch Ar Uppers
Rifles made with 20 inch AR uppers will be longer and heavier than carbine-length rifles. They will not be as light in the hand or handle as surely, but they will be more stable.
For this reason, many AR shooters prefer the longer length of a 20 inch AR upper for long-range shooting and similar competitive disciplines.
While they will not handle as well in close quarters, a rifle with a 20 inch barrel will shoot a little faster and flatter than one with a shorter barrel, as the extra length gives the bullet more time to accelerate before it leaves the bore.
The longer sight radius will also make it easier for operators to shoot the rifle accurately, but the flipside of the longer barrel is potentially complicated barrel harmonics.
The longer barrel is more likely to exhibit untoward oscillations near the muzzle end upon firing, resulting in barrel whip that can throw off the accuracy of your shots.
All in all, however, a 20 inch AR upper remains a highly popular option for home builders.
Short Barrel Rifles and AR Pistols
Now let’s cover (briefly) two other shorter options, short barrel rifles and AR pistols.
Short barrel rifles are rifles with barrels less than 16 inches. These are NFA items and getting or building one will require a lot of red tape.
AR pistols are platforms built with short barrels that are designed to be fired with one hand – not from the shoulder.
Both of these, as a result of these extremely compact profiles, can be useful for defensive applications as they are light, handle readily, and are easy to conceal.
They also give the operator the flexibility to harness the firepower of a full-sized rifle in a much more compact profile.
With that said, it is harder to shoot SBRs and AR pistols as accurately as larger, slightly heavier and therefore more stable rifles.
Where to get Your Next Assembled Upper or AR Build Kit
Whether you’re looking for a 16 or 20 inch AR upper, or a build kit for a short barreled rifle or an AR pistol, your first online visit should be to MCS Gearup.
They carry a wide range of AR parts and build kits, including lower parts kits, assembled uppers, and complete build kits that have everything you need except basically just the lower receiver.
Whatever the aim of your project, they can help you realize the end result. Visit their website for more information or get in touch with them directly today.
