Why to Buy a Pre-Assembled AR 15 Complete Upper

For new builders, the number of choices available when it comes to designing an AR 15 are almost endless. To help make your decision easier, Black Rifle Depot is here to assist. We have a wide variety of AR-15 upper assemblies to choose from, but for the beginner, we’ve selected a few that we think make the most sense, based on your specific needs.

AR 15 Upper Assembly - Deciding the What and Why

The first step in selecting an AR 15 upper assembly is deciding what exactly the purpose of your new AR 15 build is going to be. Are you looking for a range toy? Are you looking at something that you need to be compact and portable?

Whether you are looking for a practical, general-purpose AR 15 that can also pull duty as a self-defense firearm. Or perhaps looking at shooting targets at a great distance. Knowing what you are going to use the firearm for before you put together your first AR 15 is going to be a tremendous help.

Keep in mind, building an AR 15 has never been easier or more affordable for beginners. You might even decide you want to have multiple upper assemblies for different uses. There are a few things to remember such as caliber, and possibly local regulations.

That said, let’s take a brief look at just a few of the AR-15 upper assemblies that Black Rifle Depot offers. We’ll take a brief look at short, medium, and longer-range AR 15 upper assemblies.

Short-Barreled Rifles or Pistol Builds

Depending on the laws in your state and your willingness to do extra paperwork, a Short-Barreled Rifle (SBR) can make for a very handy package. Obviously, NFA rules do apply. You’ll most certainly need to research that. That said, instead of an SBR, many builders today are opting to build AR pistols (be sure to look up your local pistol definitions).

If you have decided to build yourself an AR pistol, then Black Rifle Depot offers a few different short AR 15 upper assemblies that are both affordable and reliable.

7.5" 5.56 NATO Pistol Upper Assembly

Our shortest option is a 7.5" 5.56 NATO Pistol Upper Assembly that features a 4150 CMV steel barrel, a 7" M-LOK handguard an A2 flash hider, 7075-T6 Forged Upper Receiver, a forward assist and dust cover, and our lifetime warranty from Black Rifle Depot.

This 7.5” length pistol upper assembly makes for a very fun but boisterous range gun. We run our little AR pistol with a black nitride bolt carrier group and have put just over three thousand rounds through our personal T&E gun without any hiccups. It’s a tiny package that runs and runs, and is about as much fun as you can have with a small AR pistol.

I would stress, in our experience, this is an upper assembly to get for the fun of it, above practicality. I’d also like to warn you that a 5.56 round coming out of a 7.5” upper assembly is quite loud. In fact, quite loud may even be an understatement. I’m fairly certain, that given a choice, I would NOT choose my home defense AR to have a 7.5” barrel, without opting for a silencer. As it is so loud the concussions would probably break windows and eardrums if used indoors.

That said, the next step up in length is much more practical in that regard.

10.5” 5.56 NATO Pistol Upper Assembly

If you’re still liking the idea of an AR pistol build but don’t like the idea of a super short 7.5” barrel, an obvious solution is the 10.5” 5.56 NATO Pistol Upper Assembly.

This is a length where, ballistically, with the right ammo, it could make for a very mean little defensive AR pistol. You’re only adding 3” to the gun, but that length addition, in our opinion, bumps it out of ‘range toy’ category and into an area where you could seriously consider this as a trunk or behind-the-nightstand pistol, depending on your needs.

Our 10.5” 5.56 NATO Pistol Upper Assembly has the same features as the 7.5" 5.56 NATO Pistol Upper Assembly, and paired with one of our bolts, you have a very handy, reliable and practical AR 15 pistol. Because of the added length, it may be advisable to use a second hand to steady and aim the pistol, just remember to not add a vertical grip to the handguard.

One caveat: Even at 10.5”, these upper assemblies are still quite loud. As long as you know what to expect going in…carry on.

16” AR-15 Upper Assemblies

For many first-time builders, the 16” AR-15 Upper Assemblies are the sweet spot. I’d go so far as to say, for most people, in most circumstances, a 16" upper assembly is the ideal all-around choice, especially as a first AR 15.

With this size you get the most out of the rifle from a ballistic standpoint. The gun will be softer shooting, the concussive blast present in the shorter barrels is not a huge factor, and it’s an overall very practical length for a wide variety of uses.

If questioned by first timers about what length to go with, we always recommend the 16” AR 15 upper assemblies over any other length we sell at Black Rifle Depot. Choosing a mid-length rifle to start with will give the best comparison mark for new shooters. Plus, a 16” AR 15 Rifle is an easy rifle to customize, experiment with, and enjoy.

16" 5.56 NATO Upper Assembly

Weighing just 3 pounds and 12.5 oz., the 16" 5.56 NATO Upper Assembly is a true workhorse and one of our most popular AR-15 upper assemblies.

It features a quality 5.56 Ballistic Advantage Modern Series barrel, a 15" Slim M-LOK Hand Guard .750 Steel Gas Block (QpQ Nitride), 7075-T6 Forged Upper Receiver, A2 Flash Hider (QpQ Nitride), and Standard Mil Spec Charging Handle.

Pair this upper assembly with a bolt from Black Rifle Depot and you’ve got a reliable and affordable upper assembly that is a perfect introduction to the AR-15 Platform.

16" 5.56 NATO Super Slim Upper Assembly

For a slightly slimmer and lighter option, weighing in at only 3lb 4oz. we offer the 16" 5.56 NATO Super Slim Upper Assembly. It features a 5.56 M4 Profile 1:7 Twist Barrel (QpQ Nitride), Carbine Length Gas System, our 15" Ultra-Light M-LOK Hand Guard, .750 Steel Gas Block (QpQ Nitride), 7075-T6 Forged Upper Receiver, and the Elite Muzzle Brake (QpQ Nitride).

This upper assembly does not stay in stock long whenever we replenish stock, so be sure to get on the waiting list if we are out of stock. The next upper is for those who want to buy an upper assembly that is a cut above the others.

16" Stag 15 VRST S3 5.56 Upper Assembly

For a slight step up, be sure to take a look at the Stag 16" Stag 15 VRST S3 5.56 Upper Assembly. The VRST S3 Uppers feature Stag's high quality and long-lasting durability standards, outfitted with Diamondhead's lightweight, free float 13.5" VRST Series 3 M-LOK Handguard.

The Stag 15 VRST S3 Upper features a 5.56x45mm NATO chamber 16" 1/7 chrome lined barrel with a 13.5" free float M-LOK handguard and A2 birdcage flash hider.

Also included with this upper assembly is a Mil Spec Bolt Carrier And charging Handle…so you have everything you need in one convenient and affordable package. This is an easy way to make sure you get an inclusive package that works as well as it looks.

But if you really want to get something different, that will turn everyone’s heads at the range, then you need something shockingly different.

Titan 16" .223 Wylde CHF Complete Upper Assembly (Burnt Bronze)

Another affordable and reliable “head turning” option is the APOC Armory 16" Titan .223 Wylde Cold Hammer Forged Upper Assembly. The APOC Armory Titan upper assembly comes standard with our CHF black nitride barrel. These uppers are assembled on a forged 7075-T6 anodized receiver with t-marks.

For this particular upper assembly, we went with an ultra light weight 15" free float M-LOK hand guard. In fact, we have the upper receiver and the handguard treated in “Burnt Bronze” Cerakote to ensure it turns heads!

The gas block as well as the muzzle device are black nitride treated to match the barrel. Also, included, you have your choice of black nitride or premium nickel boron BCG with extended latch charging handle.

Finally, the APOC Armory 16” also has a mid-length gas system worth noting. It’s the system I enjoy on my personal 16” rifles, as I feel it’s smoother shooting and perhaps aids in reliability.

These APOC Armory uppers have a 1" MOA Guarantee as well as unconditional lifetime warranty on all parts and labor.

Dirty Bird 16" Govt Mid 556 M-LOK Complete Upper

This Dirty Bird Industries Complete Upper features a Black Nitride 16" Sub-MOA Government Profile barrel chambered in 5.56 with a 1:7 twist. Built on a top-tier t-marked Forged Upper Receiver and finished with Dirty Bird's 15" SMRS M-LOK Handguard available in several color options.

No corners are cut when manufacturing these complete uppers. All barrels are dimpled and cold blued, use a black nitride 4140 steel gas block and a stainless-steel gas tube. The gas block set screws feature knurled cone tops and are installed using blue Loctite ensuring that no amount of firing will cause the set screws to come loose, but they will still be able to be removed for servicing if needed.

This upper assembly also has a mid-length gas system, which we love.

As far as reliability, this is an upper assembly that I trust to absolutely function when I need it to. It's an absolutely tremendous upper. Be sure to add to your order a BCG or a charging handle if you need those.

18" .223 Wylde Spiral Fluted Upper Assembly

Finally, if you’re looking for a bit longer barrel, we have you covered with the 18" .223 Wylde Spiral Fluted Upper Assembly. It features an 18" .223 Wylde Spiral Fluted 1:8 twist, Mid Length Gas System, 16.5" Keymod Hand Guard, Steel Black Nitride .750 Low Profile Gas Block, 7075-T6 Forged Upper Receiver With FA/DC, and a Competition Black Nitride Muzzle Brake.

We almost always prefer a 16” barrel for new shooters. But some feel that the 18” barrel gives you slightly less recoil, and a slight bump in velocity. Something that is appreciated by newcomers to the sport. With this in mind, an 18” can be a great choice for those who are not worried about the added weight, or storage length.

What to Do Next

No matter which AR 15 upper assembly you choose, any of the above will provide you with a strong and reliable starting point for your new AR build. If you decide to make us your supplier of choice, you can count on high quality products and five-star customer service at Black Rifle Depot. We are here to help you throughout your shopping and buying experience.