The AR-15 is one of the most versatile rifle platforms available today. By using an upper receiver chambered in 7.62x39mm, you can combine the accuracy and ergonomics of the AR-15 lower with the hard-hitting power of the AK-47's 7.62x39 cartridge. This gives you an extremely adaptable rifle for various shooting applications.

In this article, we’ll be reviewing the top options for complete 7.62x39 upper receivers and rifles to swap out with your standard AR upper, keeping in mind you would need to use magazines specifically designed for 7.62x39mm in an AR-15. We analyzed dozens of potential models in terms of reliability, accuracy potential, features, quality of construction, and overall value. These are the best picks available today.

When converting, consider the following specifics:

Bolt and Firing Pin: The bolt and firing pin for the 7.62x39mm upper are different from those used in a standard .223/5.56 AR-15. Make sure the upper assembly is complete with the correct bolt carrier group and firing pin.

Recoil and Buffer: The 7.62x39mm round produces different recoil characteristics compared to the .223/5.56. Using an appropriate buffer and spring setup can help ensure reliable cycling.

Gas System: Ensure that the gas system of your 7.62x39mm upper is properly tuned for reliable operation with the lower receiver.

How We Selected the Best 7.62×39 AR-15 Uppers and Rifles

Our recommendations come from the first-hand experiences of seasoned firearms experts. Our editorial team and community include military veterans, competitive shooters, experience working in gun shops, and dedicated hobbyists.

We have handled countless AR platform rifles and AKs over decades of combined experience. By spending so much time shooting and working with these guns, we know what to look for.

When rating the best 7.62x39 uppers and rifles, we focused on critical performance criteria. This included testing for reliability under tough conditions and gauging inherent accuracy when firing at fast-moving targets. We also closely evaluated construction quality relative to price points. Top-rated picks needed to demonstrate value for your money while avoiding common issues like failing to feed properly.

We also factored in ergonomics and shooting comfort during longer range sessions. Guns and uppers had to fit and handle well for shooters of various builds and experience levels.

By pooling our first-hand knowledge and combined with extensive research, we singled out the most versatile 7.62x39 models. These integrate sought-after qualities of both AR-15s and AKs to create unique and adaptable firearms.

Review of Top 6 AR-15 Uppers and Complete Rifles in 7.62×39

1. CMMG Mutant – Editor’s Pick

The CMMG Mutant, also known as the Mk47, offers 7.62x39mm chamberings in multiple complete rifle and pistol configurations. Renowned for its CMMG signature quality, the rifle boasts an excellent fit and finish.

The Mutant ships as a complete rifle, ready to use straight out of the box. It is available in both full-length and more compact pistol formats to suit various needs. By utilizing direct impingement operation, it combines AR-15 familiarity with the reliability and compatibility of standard AK magazines, using the abundant 7.62x39mm ammunition.

CMMG crafts the Mutant to their rigorous quality control standards, ensuring precision, consistency, and durability. The rifle is specially optimized for the ballistics of the potent 7.62x39mm round, ensuring reliable functioning and excellent accuracy under diverse shooting conditions.

Overall, the CMMG Mutant marries the best features of Eastern and Western rifle philosophies into a versatile and capable tactical package.

Features include:

• Direct Impingement operation

• Medium-taper barrel

• 15" MLOK Handguard

• A2 flash hider

• CMMG Zeroed ambidextrous charging handle

• M4 multi-position stock

• A2 pistol grip

• CMMG mil-spec trigger

• Accepts AK-style magazines

Pros:

• Ready to shoot upon delivery

• Utilizes widely available AK magazines

• Offers both rifle and pistol variants for greater shooting versatility

Cons:

• Priced higher than many competing options

2. Jacob Grey Firearms Ultralight – Best Overall Upper Receiver  

This lightweight billet upper from Jacob Grey Firearms provides great accuracy and plenty of customization potential at a reasonable price. 

The fluted 16-inch heavy barrel provides excellent accuracy while keeping weight down. It is paired with an ultra-lightweight M-LOK handguard that gives ample attachment points for accessories like lasers and flashlights. The 7075 billet aluminum receiver provides a precise fit with the barrel for enhanced consistency while allowing complex machining.

Jacob Grey includes their enhanced bolt carrier group, which features a shock-resistant extractor and reinforced firing pin. The upper ships with an ambidextrous charging handle for smooth operation from either shoulder. It’s important to note that these models are only available as part of the complete JG15 Ultralight Rifle, not as separate upper receiver components. Combined with the lightweight profile, these components make the rifle easy to handle and shoot accurately in defensive use cases.

It's a lightweight but robust package perfect for shooters wanting to customize their 7.62x39mm AR platform without breaking the bank.

Pros

• Lightweight M-LOK forend  

• Includes carrier group and charging handle

• Accurate heavy contour barrel

Cons

• Only available in pistol/SBR lengths 

3. Palmetto State Armory Gen 2 KS-47 – Best Budget Complete Rifle

The Gen 2 KS-47 from Palmetto State Armory delivers 7.62x39mm firepower in an AR-15 format at a budget-friendly price point. This innovative rifle combines the ergonomic controls and accessory capabilities gun owners love about the AR platform with the hard-hitting knockdown power of the classic AK-47 cartridge.

Reliability and affordability are the hallmarks of this complete rifle package. By incorporating the 7.62x39mm chambering into the adaptable AR-15 design, the KS-47 rifle provides exceptional versatility. The rifle runs on widely available and cost-effective AK magazines for smooth feeding. The KS-47 features comfortable Magpul MOE furniture for handling ease, along with Palmetto State's polished single-stage trigger for crisp and clean breaks.

Various barrel length and finish options are available to suit your preferences and local laws. The KS-47 isn't built for extreme precision but rather aims for minute-of-bad-guy practical accuracy for defensive applications. If you have always wanted to experience AK ballistics in America's favorite modern sporting rifle platform, the Gen 2 KS-47 warrants strong consideration with its combination of functionality, customization potential, and value.  

The only notable drawback of the design is the lack of true last-round bolt hold open due to reliance on standard AK magazines. For shooters wanting AK power at AR prices, Palmetto State Armory finds the sweet spot with their KS-47 series.

Pros 

• Great value for money

• Uses common and affordable AK mags

• Crisp, clean PSA trigger included

Cons

• Accuracy is acceptably minute-of-bad-guy  

• No bolt hold open on last round

4. Palmetto State Armory PA47 – Best Budget Upper Receiver   

The PA47 stripped upper receiver from Palmetto State Armory provides a cost-effective foundation piece to build your own custom 7.62x39mm AR rifle. This classic design combines well-proven components with the hard-hitting capabilities of the Soviet round.

Built with forged 7075-T6 aluminum, the PA47 features an optics-ready Picatinny flattop upper receiver design paired with a traditional round fixed front handguard. The barrel is a durable chrome moly vanadium steel unit, parkerized for protection. The carbine-length gas system provides reliable function. PA enhanced the rifle with their signature matte black hard coat anodized finish for exceptional wear resistance and corrosion protection even under harsh conditions.

By utilizing common components and widespread parts compatibility, the PA47 in 7.62x39mm is easy to customize over time as budgets allow. The front post sight provides an old school touch while allowing plenty of mounting options. As one of the most affordably priced ways to set up an AR in this hard-hitting Soviet caliber, the PA47 upper skips expensive bells and whistles without sacrificing ruggedness. This aims to deliver reliable functionality above all else for the working man.

Overall the no-frills design focuses on nailing down core operation and providing future upgrade potential. The beauty of the AR platform is customizing combinations until your rifle runs just the way you like it. Palmetto State Armory embraces this modularity as well as respect for classic renditions with their PA47 stripped upper receiver.

Pros

• Extremely affordable option

• Includes A2 iron sights  

• Uses widely available parts

Cons 

• Plain design with limited extras

• Few included accessories

5. CMMG Resolute MkGs – Best Pistol Caliber Carbine 9mm Upper Receiver

 

The CMMG Resolute MkGs shines as a top-tier 9mm AR pistol caliber carbine upper receiver. It brings welcome innovation to a platform often dominated by basic blowback operation. This upper utilizes a delayed blowback system with a bolt that postpones opening when fired. These cuts felt recoil while boosting reliability.

The MkGs work flawlessly with Glock pistol magazines too. This cross-compatibility brings tremendous versatility for both range training and defensive use. 

In terms of format, the Resolute MkGs mimics a standard AR-15 with familiar controls and accessory mounts. This facilitates easy transition for those used to 5.56 NATO platforms. The upper ships as a complete assembly, ready to mount on existing mil-spec lower receivers.

For AR enthusiasts seeking to augment their collection with a 9mm, the CMMG Resolute MkGs hits the mark. It delivers premium engineering and performance perfect for competitive and recreational shooting alike. The radial delayed blowback operation also sets it apart from more basic PCC options. If you want cutting-edge innovation alongside pistol caliber affordability, this versatile upper warrants a close look.

Pros

• Utilizes a radial delayed blowback system for reduced recoil and enhanced reliability.

• Compatible with Glock magazines for widespread availability and affordability.

• Includes BCG and charging handle for complete, ready-to-install convenience.

Cons

• May require specific tuning for optimal performance with various 9mm loads.

6. Radical Firearms 7.62x39mm Heavy Profile – Notable Mention

Radical Firearms offers their 7.62x39mm AR rifle as a durable, accurate option at a budget-friendly price. Designed for shooters wanting more performance than a standard AK-style rifle, it brings MIL-STD quality to the affordable AR platform.

At the heart sits a 16-inch heavy barrel with a 1:10 twist rate. This enhances the ballistic potential of the 7.62x39mm cartridge for reliable expansion and penetration. Expect versatility for both short and long-range use. 

The rifle comes equipped with a 15-inch M-LOK handguard. This creates ample room for accessories while effectively dissipating heat from prolonged firing. Up top, a full-length Picatinny rail lets you mount optics with absolute flexibility. 

By focusing on essential upgraded features over unnecessary frills, Radical Firearms keeps costs down. You still get a highly configurable rifle thanks to the M-LOK and Picatinny integration. Customize the platform to suit your specific recreational or professional needs.

Overall, Radical Firearms found a way to deliver enhanced durability and accuracy that 7.62x39mm fans want all at a reasonable price point. If you desire better-than-average AK performance without breaking the bank, this rifle warrants a close look.

Pros:

• Competitively priced

• High capacity for customization with ample room for accessories

• Precision heavy profile barrel for enhanced accuracy

Cons:

• Does not include a bolt carrier group or charging handle

Comparative Analysis: 7.62×39 vs. 5.56 NATO 

Comparing the 7.62x39mm Soviet round to the 5.56x45mm NATO standard reveals some key ballistic differences that impact real world effectiveness.

7.62x39mm   

• Bullet Diameter: 0.312′′

• Case Length: 1.52′′  

• Max Pressure: 45,010psi  

• Muzzle Velocity: ~2400 fps 

• Bullet Weight: 120-125gr

5.56 NATO   

• Bullet Diameter: 0.224′′  

• Case Length: 1.76′′

• Max Pressure: 55,114psi 

• Muzzle Velocity: ~3,000 fps   

• Bullet Weight: 55-77gr

What This Means

The 7.62x39mm fires a much heavier bullet at lower velocities compared to the 5.56 NATO’s lightweight projectile. This gives the Soviet round more energy for barrier penetration and stopping power at normal combat ranges inside 200 yards.

However, the 5.56mm retains higher velocities downrange thanks to its aerodynamic profile. This results in less bullet drop and drift for enhanced precision at longer ranges. Against unprotected targets, it is still quite devastating despite having less momentum.

Choose 7.62x39mm uppers and rifles when you prioritize stopping power and cover penetration over flat shooting. The 5.56 NATO has better trajectory for distant small targets. Either is suitable for defense, hunting, sports shooting, and tactical applications—it just depends on your needs and preferences!

Final Thoughts  

Adding a 7.62x39mm upper to your AR-15 lower or choosing one of these complete rifles gives you an extremely versatile firearm. You get to reap the benefits of the heavier Soviet caliber without losing the ergonomic controls and accessory capabilities of America’s most popular rifle platform.

Whether building a 7.62x39mm AR from scratch or just looking to change uppers, you can’t go wrong with any of these top-rated solutions we covered. They provide reliability, accuracy, and great user experience while chambering a hard-hitting round loved by legions of shooters worldwide.

Consider going with the CMMG Mk47 complete rifle if you want a premium 7.62 option ready to shoot out of the box. On a budget, the Palmetto State Armory KS-47 offers lots of value. The Radical Firearms barrel will extract extra range from the Soviet cartridge as well.

No matter what you choose, one of these top rated 7.62x39mm AR uppers or rifles will serve you well! Pair it with quality ammo and optics to unlock the full potential.

Frequently Asked Questions

How accurate is the 7.62x39mm cartridge in the AR platform?

Expect minute-of-enemy practical accuracy in the 2-3 MOA range at normal combat distances within 200 yards when using quality ammunition. The AR platform helps the Soviet round achieve respectable precision though it was not designed as an exceptionally accurate cartridge like the 6.5 Grendel. Manage your expectations, use good quality barrels and ammo, and 7.62x39mm will serve its role well.

Does the 7.62x39mm Recoil more than a 5.56 NATO AR-15?

Yes, the increased bullet mass and lower velocities of the 7.62x39mm mean it does have slightly more felt recoil. This is even more pronounced in lighter short-barreled AR pistols. The soft recoil impulse is very manageable, however, especially with a proper muzzle brake installed. Adding some extra mass to the buffer system also further mitigates recoil for faster follow up shots.

Are these uppers compatible with standard AR-15 lower receivers?

In most cases, yes. The standard AR-15 magazine well may require slight modification to properly fit AK magazines using magwell adapters. But otherwise, these uppers work with standard lower receivers. The Faxon ARAK-21 uses some proprietary parts due to its piston gas system but the rifle lower itself is standard. Just be aware, not all AR-15 triggers may have light enough hammer springs for proper ignition on hard Russian primers, so stick to standard mil-spec triggers or high-quality aftermarket ones rated specifically for 7.62x39mm use.

How does the ballistics of 7.62x39mm compare to .300 AAC Blackout?

The external dimensions of 7.62x39mm vs .300 BLK are nearly identical, as is their trajectory and overall ballistic profiles when both fire similar ~125 grain bullets. However, the increased case capacity of .300 BLK allows for higher potential velocities with heavier projectiles. .300 BLK also fits standard AR-15 magazines while 7.62x39mm requires modified magwells and dedicated AK or hybrid magazines. Both deliver lots more hitting power than 5.56 NATO, just with slightly different strengths and tradeoffs.