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What is 300 Blackout Upper? 😏
It also known as 300 BLK or 300 BO, is a specialized rifle platform designed to fire 300 AAC Blackout rounds. This platform has quickly become a favourite among many shooters due to its versatility and compatibility with multiple different ammunition types.
- 🟡 They come in a range of styles and form factors, from classic A2-style uppers to more modern flat tops and KeyMod designs.
- 🟡 Many of them are made from high-quality materials such as aluminium or steel, while others feature lightweight polymer construction.
- 🟡 The 300 AAC (Advanced Armament Corp) blackout is an intermediate cartridge designed to offer rifle performance in an AR-15 platform without major modifications.
- 🟡 It offers superior ballistics compared to the standard 5.56 NATO cartridge, making 300 BLK Uppers great for hunting and target shooting applications.
- 🟣 It provides the shooter with maximum accuracy and control, allowing them to achieve higher levels of performance.
- 🟣 They also provide increased range and lethality, allowing the shooter to engage targets at greater distances than before.
- 🟣 Additionally, these uppers are incredibly lightweight, making them easy to transport and manoeuvre quickly in any environment.
- 🟣 They are also incredibly versatile, being able to effectively fire a variety of ammunition types including supersonic, subsonic, and match-grade rounds.
Best 💣 300 Blackout Upper Receiver
1# TRYBE Defense AR-15 Pistol Upper M-LOK .300 Blackout
If you’re searching for an AR-15 pistol upper that delivers on both quality and performance, the TRYBE Defense AR-15 10.5″ Upper is a perfect choice. Featuring a high-performance 4140 CMV steel barrel with 5R rifling and a 1:8″ twist, this upper is designed for precision shooting. Additionally, the 10″ M-LOK free float rail provides a stable platform for mounting optics and other accessories. The A2 flash hider gives you added concealment, while the black nitride BCG provides reliable operation. Plus, the mil-spec charging handle ensures smooth and reliable operation. When you’re ready to take your shooting to the next level, the TRYBE Defense AR-15 10.5″ Upper is the way to go!
2# Radical Firearms 300 AAC Blackout Upper Assembly
Requiring a top-quality, law enforcement grade AR-15 upper receiver assembly that’s easy to install? Look no further than the Radical Firearms 300 AAC Blackout Upper Assembly. This flat-top receiver is ready to be mounted on any Mil-Spec AR-15 lower receiver and features a forward assist for increased accuracy and faster cool-down time. With an ejection port door for easy installation, this upper receiver assembly is a great choice for any level of budget or shooter.
3# Jacob Grey Firearms .300 Blackout Complete Upper Assembly
If you need an AR-15 that can perform in close quarters and at long range, the Jacob Grey Firearms .300 Blackout Complete Upper Assembly is a perfect choice. This versatile upper assembly features a cold hammer-forged barrel with a reliable pistol gas system, making it ideal for a wide range of applications. Whether you’re using it for home defense or hunting, you can trust the Jacob Grey 300 Blackout to get the job done.
4# Ghost Firearms Elite Complete Upper Receiver .300 Blackout
If you wish for a high-quality upper receiver for your AR-15, note the Ghost Firearms Elite Complete Upper Receiver. This top-of-the-line receiver is machined from 7075 T6 aluminum for a durable yet lightweight construction. It also features an M-Lok free float hand guard that provides ample space for mounting a variety of accessories. Plus, the included Pistol-Length Gas System ensures smooth and reliable operation. Whether you’re building a new rifle from scratch or upgrading your existing firearm, the Ghost Firearms Elite Complete Upper Receiver is a great choice.
5# Aero Precision M4E1 Threaded .300 Blackout Complete Upper Receiver
The Aero Precision M4E1 Threaded .300 Blackout Complete Upper Receiver is a faultless choice for your next lightweight build. This complete upper includes a new ATLAS S-ONE Handguard, which is designed with size and weight in mind. The proprietary ATLAS attachment system is a durable and dependable mounting platform, maintaining a slim profile while still providing the strength and stability customers have grown to love from Aero Precision handguards. With a 10″ barrel and 1-7 twist rate, this upper receiver is optimized for use with .300 AAC Blackout ammunition. The A2 Flash Hider provides recoil reduction and eliminates muzzle flash, while the M-LOK gun rail allows you to attach a variety of accessories. This upper receiver is compatible with AR-15 lower receivers and is backed by a lifetime warranty.
6# Spikes Tactical 300 Black Out Forged Upper Receiver
If you’re looking for the best way to complete your current rifle build, pay attention to the Spikes Tactical 300 Black Out 8.3in Forged Upper Receiver w/ 7in SAR3. This premium upper receiver kit comes with everything you need to take your rifle to the next level, including a high-quality M16 bolt carrier group that has been both high-pressure tested and magnetic particle inspected. The Spikes Tactical 300 Black Out 8.3in Upper Receiver Kit also features a durable 7075 T6 aluminum upper that is designed for outstanding durability and performance. All of the parts included in this kit are made from high-quality materials and several components are treated to resist corrosive elements, ensuring a long service life. Order yours today and see the difference that Spikes Tactical can make in your shooting experience!
7# Grid Defense .300 Blackout Upper Receiver
Want to purchase an upper receiver that will take your AR build to the next level? Check out the Grid Defense .300 Blackout Upper Receiver. This top-of-the-line receiver comes with an M-LOK free float handguard that provides superior accuracy and allows for the attachment of a wide variety of accessories. It’s also constructed from 7075 T6 aluminum, making it lightweight yet extremely durable. Plus, it comes with a barrel, muzzle device, and pistol-length gas system.
8# Brownells Brn-180 Gen 2 Complete Upper Receiver Assembly
Do you need a top-quality upper receiver assembly that incorporates many of the best features of the AR-18/AR-180 platform? Consider the Brownells BRN-180 Gen 2 Complete Upper Receiver Assembly. This updated version of the popular BRN-180 features an adjustable gas system, making it easier than ever to fine-tune your firearm for optimal performance. The robust and reliable gas piston operating system is inherited from the AR-18/AR-180, making this upper receiver assembly a great choice for anyone looking for maximum reliability. Whether you’re a competitive shooter, law enforcement professional, or just a passionate recreational shooter, the Brownells BRN-180 Gen 2 Complete Upper Receiver Assembly is an excellent choice. Order yours today and see for yourself!
9# Anderson Manufacturing Ar-15 Upper Receiver Assembly 300blk
The Anderson Manufacturing 300 Blackout Complete Upper Receiver is the perfect way to quickly and easily build or change an existing AR-15 to shoot the popular 300 Blackout round. The 16” barrel has a 1-8 twist rate and is Type 3 Hard Anodized – Black finished. The barrel also has a carbine length gas system with a .125 gas port, 5/8-24 threads, and comes with a 308 A2 Flash Hider. The Anderson Manufacturing 300 Blackout Complete Upper Receiver features an M4 barrel, A2 handguard, and A2 Flash Hider.
#10 Adams Arms P3 AARS Complete Upper AR-Platform 300 Blackout 12.5
The Adams Arms P3 AARS Complete Upper AR-Platform 300 Blackout 12.5 is a flawless choice for anyone searching for a precision AR upper that is ready to compete. This upper features a PROOF Research Carbon Fiber Wrapped Barrel, jet comp, ambidextrous charging handle, low mass carrier, and the signature P-Series Micro Block Adjustable piston system. With its ergonomic free float rail and superior build quality, the P3 is sure to give you the edge you need on the range or in competition. Order yours today and be prepared to dominate the competition.
#11 Adams Arms P2 AARS Complete Upper AR-Platform 300 Blackout 16″
Wishing for a complete upper that’s ready for action? Take a look at the Adams Arms P2 AARS. This upper is built on a military-spec AR platform and chambered in .300 AAC Blackout. It features a 16″ barrel with a government profile and a pistol-length gas system. The free float rail provides ample space for accessories, and the A2 flash hider helps keep muzzle flash to a minimum. Whether you’re a tactical shooter or simply someone who likes to be prepared, the P2 AARS is a great option.
#12 Brenton USA Guide 18in .300 AAC Blackout Upper Receiver
The Brenton USA Guide 18in .300 AAC Blackout Upper Receiver is a limited-series rifle that is purpose-driven in its design. It is available in Midnight, adjustable stock configuration only and includes Black Nitride carrier and bolt components as well as a 4.5 lbs single stage mil-style trigger. Limited series rifles are for rough use, and bounce around in the back of the 4×4 kind of hunter. With its .30 caliber diameter, the blackout has captured the hearts of many hog hunters. The 110 gr. Barnes and Hornady copper bullets perform very well on this platform.
#13 Primary Weapons Systems MK109 MOD 2-M Pistol .300BLK Upper Receiver
The Primary Weapons Systems MK109 MOD 2-M Pistol .300BLK Upper Receiver is a high-quality piece of firearm hardware that is superb for anybody who wants to convert their AR-15 into a powerful and effective .300 AAC Blackout rifle. With a 9.75-inch barrel and a non-adjustable gas system, this upper receiver is ideal for anyone seeking top performance from their firearm. The 1-8 twist rate ensures accuracy and reliability, while the matte black finish provides a sleek and professional look. At just 5.6 pounds, this upper receiver is also incredibly lightweight and easy to handle.
#14 Jacob Grey Firearms Ultralight 300 BO Complete Upper Assembly
Jacob Grey Ultralight Complete Upper Assembly is a top-of-the-line AR-15 complete upper assembly that won’t break the bank. This quality upper assembly is designed with the next-generation AR-15 in mind, featuring a sleek, refined look that doesn’t sacrifice the classic lines of the AR-15 platform. The Jacob Grey Ultralight Complete Upper Assembly is built around a 7075-T6 billet upper receiver that has been specifically machined and cut to reduce excess material and reinforce areas that see excess use and wear. It comes standard with the JG-designed free float 7-sided M-LOK hand-guard that is also lightweight and leaves plenty of room for customization or the addition of numerous accessories available for the AR-15 platform. The barrel is chambered in 300 Blackout with a 1:8 twist rate.
#15 American Defense Manufacturing 300 Out 10.5 Inch Barrel M-Lok Rail Upper Reciever
The American Defense Manufacturing 300 Out 10.5 Inch Barrel M-LOK Rail Upper Receiver is perfect for your next AR build. This top-of-the-line upper receiver comes complete with a Criterion Barrel and Premium Bolt Carrier Group. It also features a Raptor Charging Handle for easy operation. For added durability, this upper receiver has an ADM Nitrite finish. Plus, it comes with a Battle Comp Muzzle Device for optimum performance.
#16 POF USA P415 Edge Upper Receiver Assembly
The POF USA P415 Edge Upper Receiver Assembly is a top-of-the-line product that was designed for optimum performance in all environments. Originally developed over 15 years ago, POF USA has constantly been testing, upgrading, and improving the design to perfection. The P-415 features the E2 Extraction Technology for easy cycling during a repeated fire. It also has complete ambidextrous fire controls to cater to both right- and left-hand dominant shooters, ensuring everyone can use it comfortably. Aside from the free-floating handrail, POF has also made many other improvements to reduce the weight of the P-415, such as their all-new handguard, which reduces the size by nearly 20%.
#17 Radian Weapons Model 1 Complete Upper Receiver
The Radian Weapons Model 1 Complete Upper Receiver is the result of simple design philosophy: use the highest quality materials, precise CNC machining, and the best components available to create a weapon that seamlessly blends form and function. The Model 1 features fully ambidextrous controls, making it ideal for both left and right-handed shooters. Every Model 1 is hand-assembled by a trained gunsmith, who inspects, tests fires, and cleans the weapon to guarantee it meets the highest quality standards. No detail has been overlooked in the creation of this superior upper receiver, which is why it comes with a lifetime guarantee.
#18 CMMG, Inc RESOLUTE 300 Series Upper Receiver
The CMMG, Inc RESOLUTE 300 Series Upper Receiver Group is an excellent choice for those who refuse to compromise on quality. This upper receiver group is produced with incredibly long-lasting and reliable materials, and it will provide you with years of reliability. For a great way to make sure you are shooting with one of the best, most long-lasting upper receiver groups the shooting industry has to offer, choose the CMMG, Inc RESOLUTE 300 Series Upper Receiver Group.
#19 Stag Arms 15 Right Hand 8in .300 AAC Blackout Upper Receiver
The Stag Arms 15 Right Hand 8in .300 AAC Blackout Upper Receiver is an outstanding choice for shooters who want the power and performance of a .300 AAC Blackout in a smaller package. This Upper Receiver features an 8-inch 1-7 twist QPQ Nitride barrel, 30 caliber A2 birdcage flash hider, and Stag Arms Slimline 7in M-LOK handguard. The Stag Arms 15 Right Hand 8in .300 AAC Blackout Upper Receiver is a great choice for shooters who want the flexibility to shoot both sub-sonic and super-sonic ammunition.
#20 CBC Industries AR-15 Complete Upper Receiver Pistol Kit, 300AAC, 10.5in
Looking for a high-quality, affordable AR-15 pistol build kit? Look no further than the CBC Industries AR-15 Complete Upper Receiver Pistol Kit! The receiver is a flat top M4 Mil-Spec upper receiver forged from CNC Machined 7075-T6 Aluminum, the hardest and most durable material of any upper! The kit also includes a pistol receiver extension, standard 3 oz carbine buffer, carbine spring, castle nut, end plate, comfortable foam cheek pad, and a complete AR-15 Lower Parts Kit ready for installation in your lower receiver. With everything you need to be included in one convenient kit, there’s no excuse not to build your custom AR-15 pistol today!
#21 Spikes Tactical 300 Black Out 16in Forged Upper Receiver
If you want to get a versatile and durable upper receiver for your next rifle build, look no further than the Spikes Tactical 300 Black Out 16in Forged Upper Receiver. This receiver is crafted from Cold Hammer Forged steel for increased strength and durability, and is coated in phosphate for enhanced resistance to corrosion and wear. The .750 gas block seat and M4 feed ramps offer smooth feeding operation, while the free-floating rail and snag-free apertures make this upper a top choice for most shooters. Plus, the forward assist adds an extra element of safety to this assembly. Tested and function checked, this upper receiver is a great addition to your existing firearm.
#22 Spikes Tactical 300 Black Out 8.3in Forged Upper Receiver w/10in
The Spikes Tactical 300 Black Out 8.3in Forged Upper Receiver W/10in is a high-quality product that will provide you with the performance you need. The upper receiver is made from forged aluminum and features a black anodized finish. The barrel is 8.3 inches long and features a pistol-length gas system. The receiver also comes with a 10in BAR2 rail and Barking Spider muzzle brake.
#23 Ghost Firearms Vital .300 Blackout Upper Receiver
Wish to get ahead in the gun game? You need a powerful firearm like the Ghost Firearms Vital .300 Blackout Upper Receiver. This upper receiver is the perfect addition to your AR15 Lower Parts, providing an extended handguard that helps prevent injuries. The pistol gas system and free-floating handguard also allow you to make the most of your time behind the sight. Plus, the birdcage flash hider adds to the rugged aesthetic of your Ghost Firearms Vital .300 Blackout Upper Receiver. So make every shot count and pick up your Ghost Firearms Vital .300 Blackout Upper Receiver today.
Step-to-step Guide: To Build 300 Blackout Upper ⌛
🔴 First, you’ll need to select the right components for your Upper. This includes selecting the right upper receiver, barrel, handguard, gas system and bolt carrier group.
🔴Once you have all of the components chosen, the next step is assembling them properly and safely.
🔴 You should start by attaching your upper receiver to your lower receiver with two cross-pins. Then attach your barrel to your upper receiver using two screws or pins depending on the type of upper you chose.
🔴Once these two parts are assembled tightly together, it is time to add on any additional parts such as a handguard and gas block. The handguard needs to be mounted securely onto the barrel nut and then attached firmly onto the upper receiver with screws or pins depending again on what type of upper you chose.
🔴 After this is done, mount your gas block onto the rail of your handguard using screws or pins and then attach the gas tube from your gas block to your upper receiver.
🔴 When everything is attached securely in place you can move on to installing your bolt carrier group (BCG). Begin by placing it inside of the rear portion of your upper receiver and pushing it forward until it clicks into place. Next, install a charging handle into place and then move on to attaching a buffer tube assembly with castle nut and end plate into place as well as an adjustable stock if desired.
🔴 The final step is testing all components before taking them out for use at a range or in a match. Make sure all parts are working correctly including safety features such as trigger resetting properly when fired offhand from different positions before ever considering using it in live fire scenarios where safety is paramount above all else!
Watch this video to find more information💻
300 blackout uppers are all the rage right now, and for good reason. They offer excellent performance in a variety of settings, making them an ideal choice for just about anyone. In this article, we’ve looked at some of the best blackout uppers on the market and what makes them so great. We’ve also provided some tips to help you choose the right one for your needs. So, whether you’re looking for your first upper or you’re just looking to upgrade your current setup, we hope this article has helped you make a decision. Thanks for reading! 😊💥
Without a doubt, this is the clearest and most comprehensive article I have read on converting to or purchasing 300 BLK (and trust me – I’ve perused many). It was incredibly informative for even this 25-year veteran! Kudos to you for such an insightful piece. Thank you so much; I’ll definitely be looking out for more of your work.
Thank you for your kind words;)
This is exceptionally written and well-crafted. Thank you for your hard work!
Thank you so much!
This post is good and shows a lot of your skills. I just wonder if I can run 300 Blackout in a 5.56 lower?
You can, but you’ll have to use a 300 blackout magazine. A 300 blackout upper will also fit on any standard AR-15 lower.
Hello! What is the best 300 blackout upper for the money?
There are a lot of great 300 blackout uppers on the market, so it really depends on your budget and needs. Read the article and find one which best fits your needs and your budget.
If I had to choose, Aero is the best bang for my buck.
As a passionate gun enthusiast who lives in Florida, I proudly possess 4 300 blackout rifles and two suppressors. To list them off: an Aero Precision 10″ pistol with a pistol-length gas system; 16″ 300 BO on Stag 3g setup (also carbine length); BCA set up at 16″, again, carbine length; then finally the V7 Weapons System 8.5″ upper outfit from Aero Precision.
Decide what you’d like to use your weapon for and then proceed. All of these gun makers have solid points, it is simply an opinion from someone who adores shooting practice and reading scientific literature. While all guns shoot well, generally speaking, I can personally attest that my Aero 300 performs incredibly smoothly in comparison to the others!
Thank you for sharing your experience!
If you’re looking to save money and still get the best quality parts, Black Friday is your go-to! But if a bargain is more important than the highest quality, check out Brownells or trybe. When it comes to purchasing an upper though, don’t hold back; there’s no rationale for waiting around when the budget isn’t an issue.
Greetings:)! I want to reply to the user King
It might be difficult to come up with a specific complete 300blk upper but bear in mind that not all uppers are created equal. Many people and manufacturers erroneously treat the 300blk caliber like any other – this is incorrect. To get optimal performance from your setup, you should look for an upper of 7″–8″ length with a 1:5 twist rate and adjustable gas block. It’s true that there are many uppers out there which may seem to work fine, however, few will do it optimally or reliably enough for long-term use.
Thanks, but you can use “Reply” button to answer directly to the comment next time 🙂
GD! Help me! Can I put a 300 Blackout Upper on my AR-15?
The 300 Blackout is a cartridge that was designed specifically for the AR-15. As such, it can be used with any upper receiver that is intended for use with an AR-15. This includes both standard and 300 Blackout-specific upper receivers.