So you want to build with a short barrel upper. Whether you’re looking at making an AR15 pistol or some species of SBR, in the spirit of fairness we have to admit that there are not only advantages, but a few drawbacks.
This short article will take a closer look at some of these.
Advantages of Building with a Short Barrel Upper
If you’re considering building an AR platform with a short barrel upper, these are some of the advantages you may reap:
- Lighter weight: No matter how you spin it, building with a short barrel upper is going to shave some ounces off the overall build. Even if you get a fluted barrel 16” or longer, it’s not going to be as light or handle as well as a barrel that’s shorter, period.
- Easier concealability: The shorter barrel results in a shorter overall length and greater overall concealability. This makes builds made with short barrel uppers better as truck guns, for defensive applications in most scenarios, and so on and so forth.
- Better practicality in close-quarters engagements: A smaller build is naturally going to offer the bearer advantages in closer quarters. The shorter barrel is easier to manipulate and handle, and will respond better to rapid movements, making it superior in such engagements.
- Better barrel harmonics: This is a tenable argument but it should be made nonetheless. A pervasive myth states that longer barrels are inherently more accurate. This is not necessarily true. A longer barrel is more likely to have inconsistent harmonics resulting in barrel “whip” that can adversely impact accuracy. Rather, the problem is that it is harder for shooters to shoot platforms with shorter barrels accurately; not that the tool itself is inaccurate.
Now for the Not So Welcome News
With all of this said and done, there are some drawbacks associated with short barrel uppers. They might not be for you if any of the following is a turn off.
- Red tape: One way or the other, building with a short barrel upper, especially if you intend to make an SBR and not an AR15 pistol, is potentially going to be problematic. For one, SBRs are considered NFA items, which means you’ll need to submit extra paperwork and pay for an extra tax stamp. For another, states have their own separate regulations that can be prohibitive.
- Less room for expandability: Since both SBRs and AR15 pistol uppers are shorter, there is less room on the handguard for expanding the platform. Not a huge detractor but still worth bringing up.
- More muzzle pop: The shorter barrel gives propellant less time to deflagrate in the chamber and bore before the bullet leaves the barrel. That means there’s way more muzzle pop with short barrel uppers. Not good for your hearing or for the action, especially if you run suppressed.
- Less power: Because of the exact same conditions mentioned above (less time for propellant to deflagrate) and because the bullet has less time to accelerate before leaving the barrel, muzzle velocities and therefore overall power will be lower with short barrel uppers, albeit marginally.
- Potentially less accuracy: A shorter barrel, though the thing itself is not less accurate, may be harder for some shooters to aim and fire accurately, in part due to the shorter sight radius. That can change with practice and drilling, however.
Where to Get a Short Barrel Upper
If you’re looking for a collection of high-quality short barrel uppers in a wide range of lengths and chamberings, visit MCS Gearup. You can also contact them directly or consult their blog for more information and helpful insight.
