Best .300 Blackout Uppers: Superior Performance – [2024] Guide

Best 300 blackout upper receiver

AR 15 has been well-established to be one of the best gun deals you can get your hands on, from its reliability, flexibility and compatibility with a wide range of quality upper receivers for your 300 blackout. 

Generally, many gun enthusiasts are a huge fan to purchase .300 Blackout upper which works perfectly with their AR 15 firearms. The 300 Blackout has been renowned as high quality AR components due to its direct compatibility with the standard AR 15 rifles which includes the standard 5.56/223 AR 15 components.

The list of components includes bolt carrier groups, uppers and lower receivers, magazines, buffers, rails, stocks, buffer assemblies and so on. Regardless, the barrel and gas system may have to  be changed to use this caliber with your AR-15. Do not worry, it is a relatively easy conversion!

Lucky for you, we have an article and section on the best 300 blackout upper receiver you can break down and get your hands on the bolt carrier group within the market. We’d list down the complete buyers guide and the best 300 blackout upper which are offered by the manufacturers in the market. 

How to Choose the Best 300 Blackout Upper?

Choosing the best 300 blackout uppers may be more straightforward and less complicated than you think it is. Lucky for you, we have prepared a series of questions as a checklist to identify the best 300 blackout upper. 

There are just three simple questions you need to ask yourself:

  1. Does it require additional parts for it to function?
  2. What is the best 300 Blackout barrel length?
  3. What type of handguard do you want for your 300 blackout?

These questions are merely the tip of the iceberg as a buyer’s guide to purchase the best .300 Blackout Upper where you could explore further such as the manufacturing process but it may be deemed unnecessary by some reviews.

Fret not, if you proceed to buying a .300 blackout upper even from the most affordable manufacturers that will be discussed below – you will not be disappointed because the market is filled with the best gun deals for you to consider. 

Does it Require Additional Parts for it to Function?

Well, it depends because the majority of the AR 15 uppers sold are pretty comprehensive which come with all of the parts that you require for your 300 blackout. These AR 15 uppers are super easy to fix where you could easily attach it to a lower receiver and load into a magazine and begin shooting.

However, sometimes even the best .300 Blackout upper does not come with certain parts such as the bolt carrier group and the charging handles. So, you have to buy the bolt carrier group and charging handle separately which can be slightly inconvenient but they are mostly very accessible within the market.

Most often than not, remember that the best gun deals which feature the best .300 blackout uppers which are cheaper than other upper receivers usually do not come equipped with the required parts. 

For your information, these .300 blackout uppers are produced and sold in such a manner to provide the shooters with flexibility and creativity to optimize the performance of your AR 15 uppers. 

For instance, most people tend to prefer a particular brand of charging handle like Radian Weapon so most people prefer to purchase a .300 Blackout upper without the charging handle. This is because to avoid having an additional factory charging handle of the .300 blk which would be lying around.

As for the bolt carrier group of your .300 blackout, most people prefer to purchase a particular brand of bolt carrier group as a matter of personal preference. For example, brands such as Radians Weapons, Bravo Company or Brownells are well known for the high-quality of their bolt carrier group. 

The bottom line is that you can mix and match with the preferred option of your bolt carrier group or charging handle to go with the best .300 blackout upper to give you the best overall shooting experience  

However, if you’re an avid shooter who prefers a hassle-free option then we’d suggest looking into a complete upper which comes ready with bolt carrier group and charging handle. This complete upper is great in saving your time and effort in comparing the features of the bolt carrier group or charging handle.

What’s the Most Suitable 300 Blackout Barrel Length?

Even with a great 300 Blackout upper, you’d still need to figure out the best 300 Blackout length of barrel and gas system for your AR 15 which is a crucial element of your .300 blk. 

For starters, there are various barrels ranging from 5 inches to 16 inches for your 300 Blackout uppers. The difference of barrel length is very important which affects the performance of your .300 blk.

Furthermore, longer barrels are excellent as they are capable of producing high energy in your bullets which translates to higher killing power and suitable for longer range shootings.

Adding on, longer barrels will inevitably increase substantial weight to your firearm which may make it difficult to maneuver and carry. As such, most people prefer to opt for shorter barrels for your guns for this particular reason.

As for firearms enthusiasts searching for a 300 Blackout upper, we would highly recommend the 7 inch barrel or the 12 inch barrel for your 300 blackout. 

This is because short barrels are light in weight and smaller in size which would reduce the overall weight of your rifle but it would also impact and reduce the energy of your bullet being fired significantly. Contrastingly, the 12 inch barrel is definitely longer in length and would boost your energy and muzzle velocity of the bullet of your firearm.

The barrels ranging from 7-12 inches are ideal but as to which specific barrel greatly depends on your personal preferences, budget and usages. However, we do prefer a barrel which is about 7-8 inch on 300 Blackout rifles which would accord the most ergonomic and compact features.

In addition to that, we tend to prefer attaching a suppressor to our 300 Blackout rifles so a short-barrel AR 15 would do the trick to achieve optimum short barreled rifles. 

Unfortunately, take note that even a short barrel has its downside which is these barrels on your AR 15 would make the face of the shooter to be in closer proximity to the muzzle.

So, you should really swap barrels if you’re looking to shoot many shots because of the high pressure, gas and potential powder which would hit the face of the shooter from the shots. Lucky for you, there is a silver lining as this is usually the case for 5.56/.223 AR-15 uppers rather than the 300 Blackout uppers.

The .300 blk is well-designed to release high pressure from short barrels by burning up its propellant so lesser impact is produced which includes lesser muzzle energy and less powder hitting your face.

If you are contemplating using a suppressor, this will not be a problem for 5.56 or 300 Blackout. The suppressor works by pushing the gas further from your face so it will be less problematic. 

Once you figure the ideal inch barrel to purchase for your new barrel, we would highly recommend you to look into your twist rate which should run about 1:5 or 1:7. To make things simpler, this translates that the bullet will rotate once per 5 or 7 inch barrel which is designed specifically to increase accuracy of the .300 blk bullet.

What Type of Handguard Do You Want?

A handguard of an AR 15 is a metal tube or plastic tube which wraps around the area of the barrel closest to the shooter.

As for the handguard which is made of metal, it is commonly referred to as the “rail.” Regardless, the handguards of your firearm can be broadly divided into 2 categories namely, the non-free floating or drop-in handguards and free-floating handguards.

A non-free floating handguard is one that works by directly touching the barrels.These handguards tend to be cheap which can be commonly found in your budget-friendly AR 15. However, these cheap handguards do have its downsides as they would break down faster, overheat easily and low accuracy as compared to free-floating handguards. 

As for the free floating handguard, it does not come in contact with the barrel which explains the name as it remains free floating within the handguard. We would recommend you purchase the free floating handguard if you do have the budget for it because it is certainly worth the investment. 

Once you’ve decided which type of handguard to purchase, you’ve to decide the type of attachment system to go with for the handguard of your choice for your firearm. 

For starters, most of the handguards which are available tend to have holes to allow various types of attachments of accessories such as scopes, lasers, lights and so on to upgrade your rifles. 

Here is the list of types of attachments to consider for your gun:

  1. M-Lok
  2. Keymod
  3. Picatinny
  4. Proprietary
  5. No attachment system

Many people prefer the M-Lok and Keymod as their top-rated choice of attachment because these methods are lightweight, more durable and do not impair the performance of your rifle. 

As for those who are clueless on the types of attachment systems, M-Lok is equipped with a series of rectangular holes cut on the handguard itself whereas Keymod rail systems have keyhole-shaped holes instead.

These two different types of systems work perfectly however, Naval Surface Warfare Center revealed that the M-Lok system is more durable and secure in attaching accessories through their testing. 

Other than that, picatinny is a much older system which has raised grooves. This picatinny rail is easy to use, highly durable and has a higher accuracy of optics being offered than other attachment systems available. However, these rails are heavy in weight which can be bulky to handle. 

Most AR 15 uppers are accompanied with a picatinny rail at the top where you would commonly see the optics being mounted. Simultaneously, you would see either M-Lok or Keymod rail systems at the sides and the base of the handguard. 

As such, we would strongly recommend you to opt for a free-floating handguard with M-Lok which offers better durability, higher accuracy and better securement of accessories as explained above.

Our List of the Best 300 Blackout Uppers

1. PSA 10.5″ Pistol Length 300AAC Blackout Upper Receiver

Best 300 blackout upper receiver


  • Barrel Length: 10.5″
  • Twist Rate: 1:8
  • Diameter at Gas Block: .750
  • Gas Block Type: Low-profile
  • Muzzle Device: A2 Style Flash Hider
  • Receiver Material: Forged 7075 T6
  • Handguard Type: Lightweight M-Lok 9″ Free Float Rail
  • Bolt Carrier Group Included: Yes
  • Overall Length: 19.5″


When looking for the best 300 blackout upper, there’s one brand that is impossible to miss out – PSA (Palmetto State Armory). Regardless of your ideal 300 blackout build, you’ll be able to find just the right upper from PSA. 

PSA is generally known to be one of the best budget friendly and reliable brands in the United States. This is especially the case when looking for gun parts like the 300 blackout uppers online. 

While all PSA blackout uppers are of excellent quality, we are going to cover the 10.5” variant in our review today. Coming with a 10.5” Chrome Moly vanadium steel barrel, it makes it one of the most durable uppers on the market for the 300 blackout. 

The upper is also phosphate coated and comes with a 1 in 8” twist rate. The pistol length gas barrel is finished off with a 9” MLOK lightweight rail. We find the 10.5” length to be ideal as it hits the sweet spot when it comes to barrel lengths.

Forged with 7075-T6 A3, this 300 blackout upper is made to mil-specs. Along with the hardboard anodized black coating, it screams durability. These uppers are made right here in the USA by a mil spec manufacturer and that’s when you know you are looking at some of the best and most reliable blackout uppers on the market. 

In relation to the bolt, it’s made from Mil-spec shot penned carpenter 158 steel. That’s some of the best material you’ll be able to find on a 300 blackout upper receiver these days. Coming with a gas key that’s secured with grade 8 fasteners and staked per mil spec. Furthermore, the bolt carrier on this upper is parkerized outside and chrome lined on the inside. 

Why you’ll like this product 

You are looking for the best value. PSA having been known to be one of the most reliable and budget friendly brands within the market, it should come as no surprise that the PSA 10.5” 300 BLK upper receiver offers the best bang per buck that you’ll be able to find in 2022. Despite having a tight budget, you’ll still be able to get your hands on some of the best made 300 blackout uppers.

Why you might not like this product 

You want an expensive upper with all the bells and whistles. While it already features some of the best specs you’ll be able to find on a 300 blackout upper, it does not come with all the fancy bells and whistles like an $800 300 Blackout upper would. That said, for a $300 blackout upper receiver, there’s not much to nitpick about on PSA here. 

2. Aero Precision M4E1 Enhanced 10″ Complete Upper 

Best 300 blackout upper receiver


  • Barrel Length: 10″
  • Twist: 1 in 7
  • Muzzle: 5/8×24 Threaded
  • Finish: QPQ corrosion resistant finish both inside and out
  • Pistol Length Gas System 
  • Weight: 21oz
  • M4 Barrel Extension


In searching for the best 300 blackout upper, you would certainly come across the manufacturer named Aero Precision being one of the best companies which offer high quality and modern uppers. Aero Precision M4E1 is designed to be very versatile which comes in 8, 10 and 16 inch barrels to choose from for your .300 blackout round. 

However, we would focus on the 10″ Complete Upper  in relation to the Aero Precision .300 Blackout Upper because this 10 inch barrel is suitable for your AR pistol or any short barreled rifles. 

This Aero Precision .300 Blackout Upper is forged from 7075 T6 aluminum, which accord high durability and reliability. Furthermore, this .300 Blackout upper has undergone HP and MPI testing to ensure that this upper receiver group can withstand high pressure especially under heavy usage.

Moreover, this further enhances the reliability and durability of this .300 blackout upper which would ensure the lifespan of the product where you could use it for a longer period of time.

As for those who prioritize aesthetics, this .300 blackout upper is made out of Matte black hard coat anodized Mil 8625 Type 3 Class 2 and comes with laser engraved T-marks which gives you that sleek and a very clean design.

In addition to that, this upper receiver comes with M4 barrel extension which allows you to counter resistance which is able to increase the muzzle energy of the bullets. 

This .300 Blackout upper comes with a 1 in 7” twist rate which allows higher accuracy even with heavier bullets hence, this guarantees the performance of your rifles. Furthermore, this upper receiver comes with a low profile gas block and pistol length gas tube that indicates minimum space is taken up on the barrel of your firearms which can reduce recoil felt. 

Why you’ll like this product 

You are looking for an upper which comes with a handguard. This Aero Precision upper receiver is the best option for you if you’re looking for a convenient and hassle-free option. It would certainly save you a great amount of time as it comes equipped with an enhanced handguard of your choice. Adding on, the product comes assembled with a port door and forward assist.

You are looking for an upper which is compatible with your AR 15 or M16 components. This .300 blackout upper is highly compatible with the standard components of AR 15 or M16 which gives you flexibility in customizing your perfect rifle.

Why you might not like this product 

You want a blackout upper with bolt carrier groups and charging handle. While it comes with a handguard, this blackout upper does not come with a bolt carrier group and charging handle but you’d purchase them easily as an add-on option when checking out your shopping cart on their website.

With that being said, the absence of a bolt carrier group and charging handle allows you to customize your .300 blackout to cater your personal preferences.

3. Radical Firearms 8.5 in. 300 Blackout AAC Upper

Best 300 blackout upper receiver


  • Barrel Length: 8.5″
  • Twist: 1 in 7
  • Pistol Length Gas System
  • 5/8×24 Threaded Muzzle
  • Color : Black
  • Cartridge : .300 AAC Blackout


We are very sure you have come across the brand, Radical Firearms among the reviews in finding the best .300 blackout upper. Radical Firearms has been long-established as one of the most affordable manufacturers in the market that offers a wide and great selection of firearms and accessories which includes the best .300 blackout upper.

With the extensive range of blackout upper offered by Radical Firearms, we would touch on specifically the 8.5” 300 blk upper which is a law-enforcement grade upper receiver kit.

These .300 blackout uppers come fully equipped with forward assist, barrel nut, ejection port door and 8.5 inch HBAR profile barrel, A2 flash hider and even a forward guard shield free-float handguard. This particular .300 blackout upper is one of the most comprehensive packages you can purchase for a reasonable price. 

In addition to that, this .300 blackout upper is tested and verified with subsonic rounds which ensure a high-quality, extremely reliable and highly accurate upper for your gun. This quality upper will certainly impress the well-experienced shooters and also, new shooters which are new to target shooting.

This .300 Blackout upper comes with a 1 in 7” twist rate which allows higher accuracy even with heavier bullets hence, this guarantees the performance of your rifles.

Why you’ll like this product 

You are looking for a drop-in installation. This would ensure the ease of installation as you can manually latch your upper onto your AR 15 lower receiver effortlessly and in a nick of time. With this drop-in installation, you do not have to spend additional resources and time to engage a gunsmith because you could easily install the AR 15 upper at the comfort of your own home.

You are looking for various mounting options for additional attachments and optics. This particular AR 15 upper is highly compatible with other mounting options so you could easily upgrade to any accessories of your choice for your gun. This allows a full-customization of your gun to cater your personal preferences, usages and budget. 

Why you might not like this product 

You want a non-free floating handguard for your gun. While it includes a series of accessories that includes the free-floating handguard which is capable of keeping your hands cool during crossfires which does not interfere with the performance of your barrel.

However, if you are a shooter who prefers non-free floating handguards then this upper receiver group may not be for you..

4. VLTOR Polylithic 

Best 300 blackout upper receiver


  • Color: Black
  • Finish: Anodized
  • M203 barrel mounting compatible
  • Compatible with all Mil-Spec AR-15 parts and accessories 
  • Aircraft-grade aluminum construction
  • Hardened to T6 specifications 


In recent times, the brand, VLTOR has been dominating the upper market by producing more robust, innovative and stronger uppers within the market.

As for this section, we would review one of VLTOR’s most innovative and creative products which is the Versatile Interface Structure (VIS) upper assembly. This assembly kit for your gun has brought about magnificent structural improvements in relation of strength and levels of accuracy. 

This is because this .300 blackout upper overcomes various issues that are commonly found into the traditional 2 piece designs. As such for those who opt for VLTOR’s upper, you would be able to experience the advantages of a free-floating barrel and a solid railed forend. 

These .300 blackout uppers are equipped with a proprietary system which essentially is a single piece of upper along with the rail system that translates to high durability and great strength.

Adding to that, the rail is free-floating and made from the Keymod system. Not to forget that the exterior has a hard coat anodized along with the aircraft-grade aluminum construction which provides resistance to rust and natural weather. 

However, you must install the barrel using a proprietary barrel wrench. Lucky for you, the  proprietary barrel wrench comes together with the upper which is quite straightforward to use so you can tighten and loosen the barrel of your gun accordingly. 

Why you’ll like this product 

You are looking for a strong upper. The aluminum used to construct the upper is aircraft-grade which makes the strength impeccable. This would certainly ensure the lifespan, reliability and quality of the .300 blackout upper given the continuous efforts by VLTOR to improve the quality of their range of products.

You are looking for a polylithic design. This polylithic design allows the standard upper and the handguard to come together as a single unit which makes it easier to carry and use. Furthermore, the structural differences would increase the accuracy and performance of your guns. 

Why you might not like this product 

You prefer to purchase from a manufacturer which is more established. Well, do not mistaken because VLTOR is certainly a reliable and trustworthy brand but it may be a relatively new brand as compared to its competitors such as Aero Precision, Brownells and Palmetto State Armory.

5. Bravo Company 9″ .300 Blackout Uppers

Best 300 blackout upper receiver


  • Barrel Length: 9″
  • Barrel Material: 11595E Spec Steel
  • Barrel Finish: Manganese Phosphate (Mil-Spec A-A-59267)
  • Weight: 2.2 lbs
  • Twist Rate: 1:7
  • Gas System: Pistol
  • Muzzle Device: BCM Comp Mod 1 (762/300BLK)
  • Muzzle Threads: 5/8×24
  • Handguard: MCMR-8


In deciding on the best .300 blackout upper to buy, you would certainly want to consider the brand,  Bravo Company which is well-known for their assured quality and constantly striving for excellence for their wide variety of aftermarket parts through their research and development efforts.

Besides that, Bravo Company is very meticulous in their quality control efforts which can reassure the quality of their products, in particular, their uppers. 

Originally, Bravo Company started off as an authorized reseller at retail outlets that sell some of the best .300 blackout uppers in the market to their customers. However, Bravo Company proceeded into venturing manufacturing their own aftermarket parts to compete with some of the best companies in comparison.

Of course, this includes a .300 blk upper that comes in various configurations to cater your personal preferences, usage and budget to compete with other quality upper. 

This barrel is made out of 11595E spec steel, which is enhanced by manganese phosphate finishing to give it an additional layer of protection against any unwanted scratches and rust. Furthermore, the bore and chamber are chrome lined which makes it incredibly durable, more heat resistant and less prone to corrosion.

Moreover, these uppers come with a MCMR-8 handguard, sling mount, and 3″ picatinny rail which would give you your money’s worth. 

This .300 Blackout upper comes with a 1 in 7” twist rate which allows higher accuracy even with heavier bullets hence, this guarantees the performance of your rifles.

Other than that, the upper is equipped with a taper barrel which is designed for maximum performance, optimal weight and balance. In addition to that, this barrel profile is situated close to the chamber of the rifle which could increase heat dissipation and promote strength of the rifle. 

Why you’ll like this product 

You are looking for a quality upper. Bravo Company will certainly not disappoint in terms of quality assurance which has always been their top priority since the beginning of times. However, each upper has its own respective instructions and after-care instructions that ideally should be followed to ensure their quality is preserved for an extended period of time.

You are looking for a MCMR-8 handguard. This upper is equipped with MCMR-8 handguard to allow you to ease the load from your barrels to assist in highly accurate shoots. Besides this, you do not have to spend any additional time in comparing other handguards which are available in the market because this is one of the best quality you can get your hands on to work with your gun. 

Why you might not like this product 

You want a blackout upper with bolt carrier groups and charging handle. While it comes with a handguard, this blackout upper does not come with a bolt carrier group and charging handle but you’d purchase them easily as an add-on option when checking out your shopping cart on their website.

With that being said, the absence of a bolt carrier group and charging handle allows you to customize your .300 blackout to cater your personal preferences.

6. DRD Tactical M4 Upper Assembly 14.5″

Best 300 blackout upper receiver


  • DRD M4 Upper Assembly 14.5″ 5.56 NATO AR-15 Barrel/ Carbine Length Gas System
  • Picatinny Rail at 12 and 6 o’clock
  • Uses DRD Tactical Barrel Nut, Gas Block and Gas Tube. Barrel Nut is bolted on and is not a takedown version.
  • 1/2×28 muzzle threads
  • 1/7 twist
  • Parkerized Finish
  • A2 Flash Hider


The brand DRD Tactical emerged after being challenged to build a 7.62mm rifle to fulfill the whitepaper request for the Clandestine Sniper Rifle project listed by Joint and Special Operations Program.

Through this, DRD Tactical managed to secure 2 patents in relation to the quick barrel change and internal recoil system through tremendous amounts of testing which has revolutionized the products released.

In addition to that, DRD Tactical is known for producing handcrafted firearms in the United States rather than producing them in mass production to preserve quality to its customers and uphold their integrity. 

This upper has parkerized finish which acts as an additional layer of protection against corrosion and rust. In turn, this ensures the quality and lifespan of the upper.  This .300 Blackout upper comes with a 1 in 7” twist rate which allows high accurate shots even with heavier bullets to ensure the most optimum performance of your rifles.

Adding on, this upper comes with A2 flash hider to reduce any unwanted flash and preserve your night vision of your rifle.

 Why you’ll like this product 

You are looking for a quality upper. DRD Tactical is well-known for their craftsmanship in creating high-quality products in particular, their uppers which has always been their top priority

Why you might not like this product 

You want a blackout upper with bolt carrier groups and charging handle. While it comes with a comprehensive series of features, this blackout upper does not come with a bolt carrier group and charging handle but you’d purchase them separately. With that being said, the absence of these parts allows you to customize your .300 blackout to cater your personal preferences.


In conclusion, finding the best 300 Blackout upper for your firearm build is crucial for unlocking peak performance and versatility. By considering factors such as barrel length, twist rate, build quality, compatibility, and trusted brands, you can make an informed decision.

Whether you prioritize close-quarters shooting, suppressed firearms, or overall accuracy, the right 300 Blackout upper will enhance your shooting experience.

Do remember to stay updated with local laws and regulations, and always prioritize safety. With the knowledge gained from this guide, you are now ready to choose the perfect 300 Blackout upper to take your firearm to the next level. Enjoy the power and versatility of the 300 Blackout cartridge and maximize your shooting potential.


Why should I consider a 300 Blackout upper?

300 Blackout offers versatility, allowing you to shoot both supersonic and subsonic ammunition. It excels in short-barreled rifles and is ideal for close-quarters shooting and suppressed firearms.

What factors should I consider when choosing a 300 Blackout upper receiver?

Look for factors like barrel length, twist rate, build quality, compatibility with your lower receiver, handguard options, suppressor compatibility, trusted brands, and user reviews.

Are there any popular brands known for producing quality 300 Blackout AAC uppers?

Yes, some reputable brands include Aero Precision, Palmetto State Armory, Seekins Precision, Spike’s Tactical, and Daniel Defense, among others. These brands are known for their reliable products.

Can I easily install an upper for .300 Blackout on my existing lower receiver?

Yes, as long as your lower receiver is compatible with AR-15 pattern uppers, you can typically install a 300 Blackout upper with ease. Ensure compatibility and consider seeking professional assistance if needed.

Are there any legal considerations when using uppers for the .300 Blackout AAC rounds ?

It’s important to comply with all federal, state, and local laws regarding barrel length, overall length, and any other regulations pertaining to firearms and ammunition in your area.

Remember, always prioritize safety, follow proper firearm handling practices, and stay informed about relevant laws and regulations.

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