One of the shortest common barrel lengths for ARPs is 5 inches, but not all builders choose a 5 inch AR pistol upper for their builds. As with all things in firearm engineering, and in life, there are benefits and tradeoffs to every choice. 

So, with that said, let’s put 5 inch AR pistol uppers under a microscope for a moment to see what sorts of advantages they offer enterprising shooters that build with them. 

The Positive Side

One of the main advantages of an ARP in general is that a shorter upper results in a smaller, lighter, more compact and more maneuverable platform. That is front and center right here: 

• Smaller size and weight: Building with a 5 inch AR pistol upper will produce one of the smallest ARPs possible, which will give you a small, light, easy-handling AR pistol for defensive applications of all sorts. 
• Easier handling in tight quarters: An ARP will handle a lot more like a handgun than other AR pistols with longer barrels, making them potentially better for defensive engagements, especially in tight quarters, such as inside a home. 
• Rifle firepower in a pistol footprint: Assuming your ARP is chambered in 5.56, a 5 inch AR pistol upper will give you a lot more power than most handguns, in a similarly sized footprint. 
• Easier concealment: Because 5 inch ARPs are some of the smallest out there, this profile will be easier to conceal in a trunk, a drawer, a small case, or in any other confined space, making it potentially and circumstantially better than other larger ARPs.

The Drawbacks

Now that we’ve covered the potential advantages of 5 inch AR pistol uppers, let’s look at some shortcomings: 

• A shorter barrel will produce a lower muzzle velocity and less muzzle energy.
• The shorter sight radius is less forgiving, affecting accuracy when shooting over irons. 
• 5 inch ARPs will produce a lot of recoil, muzzle flip, and potentially port pop.

There are others, but these three are likely the biggest ones. 

Other Common Options 

A 5 inch ARP is not your only option. You should also consider some of the following: 

• 5 inches: The 7.5 inch configuration is actually fairly common for ARP builds and will result in a light, compact build that delivers more muzzle energy than the former.
• 10 inches: An ARP with a 10 inch barrel will be heavier and less nimble than a 5 inch ARP, but will produce more muzzle energy, less recoil, and offer a more forgiving sight radius. 

Switch Up the Chambering

If you don’t want to address the potential shortcoming of an ARP built with a 5 inch AR pistol upper, consider changing the chambering. 

For instance, a handgun cartridge like 9mm will perform well out of a shorter barrel and rectify some of the concerns associated with shorter barrels. Of course, at that point, then, there isn’t much reason to build an ARP when you could just get a conventional handgun. 

You could also opt for a different rifle chambering like .300 BLK or 7.62 Soviet, both of which perform very well from shorter barrels, unlike 5.56. They actually also produce more stopping power than the latter.

Where to Get a 5 Inch AR Pistol Upper

Looking for assembled uppers for ARP builds in a variety of lengths? Visit MCS Gearup. They carry a wide range of AR15 pistol uppers, including assembled uppers and other parts. Visit their website and get in touch with them if you have any questions before you buy.

For more information about Skeletonized Ar 15 and Mck Accessories Please visit: MCS Gearup.