It’s fair to say that nailing the ideal upper receiver group could well be considered a linchpin when it comes to your AR-15. Take it from me: that upper is a pivotal player in ensuring that the bolt and barrel have a solid meet-up, leaving you cradling either a precision tool you can rely on or a piece that’s pretty much a standing invitation to exasperation.
If you’re hankering for an AR that excels in tack-driving accuracy, all-around versatility, or holding its own in the tight confines of home defense scenarios, rest assured there’s an upper tailor-made for your aspirations. But the real head-scratcher is, how does one sift through the options to land the cream of the crop?
Branching Out With a New Rifle Build
Diving into a deluge of AR-15 upper receiver to craft a fresh rifle is a path well-trodden. Your journey might take you through a selection of barrels, various aesthetics to fit your style, not to mention a pick of operating systems to dial in the handling just how you fancy.
These fine-grained choices are precisely why snapping up an upper receiver is a hot ticket for those looking to be the architects of their firearm fate. Kick off with an upper receiver that’s got your name on it, and you’re on your way to assembling an AR-15 that’s the embodiment of your shooting dream sheet.
Leveling Up With Added Functionality
Then there’s the scenario where folks might have an intact lower or a full-on rifle that’s lost its luster in fulfilling their shooting checklist.
In such a scenario, it’s a no-brainer to pick up a new upper receiver that can rejuvenate their rifle’s performance to match their evolving demands.
Say your current AR boasts a 16-inch barrel, but your crosshairs are set on something with a longer reach for those distance shots, or perhaps you’re gearing up for a pivot towards .300 Blackout for its prowess in a home-defense blueprint.
It’s in those moments that upgrading with a new upper receiver becomes a savvy way to sample fresh functionalities sans the commitment to an entirely new firearm.
Important AR Upper Features
Central to the storied legacy of Eugene Stoner’s AR-10/AR-15 design, now venerable at nearly seven decades old, you’ll find the ingenious utilization of a dual-component receiver setup, comprising an upper and lower segment.
The full-fledged upper ensemble traditionally encapsulates not only the receiver framework but also the barrel, the operational gas system, a muzzle flash suppressor, the frontal sight rig, the rail system or handguards, a slip ring, the hatch for cartridge ejection and the dust cover, the manual charging handle, the bolt carrier group, and, when it comes to models akin to the M4-style carbines, the forward assist assembly.
As for the lower counterparts, they’re the crucial housing for your trigger apparatus, the magazine well & its corresponding release mechanism, the bolt catch, the firearm’s grip, along with a vast constellation of various springs and pins. It’s an entire microcosm often procurable as a singular lower parts kit, commonly abbreviated as LPK.
Let’s dive into a trio of pivotal characteristics to look out for in your AR upper:
1. GRADE OF ALUMINUM
It’s the norm for uppers to be constructed from aircraft-caliber aluminum (a nod to Stoner’s formative days at the helm of the Fairchild Aviation-connected ArmaLite Rifle project) and they’re generally presented in two grades: 6061-T651 and 7075-T651. It’s the latter that’s typically held in higher regard owing to its almost doubled tensile and yield strength capacities, presenting this advantage without a significant uptick in mass.
2. BILLET OR FORGED
Uppers manifest in two primary forms: forged and billet. Forging is the more prevalent (and economically viable) practice, while billet uppers are often the choice for those diving into the realms of custom gun builds due time-intensive machining endeavors they necessitate.
3. BARREL LENGTH
The versatile, truly modular nature of AR-styled firearms presents owners the luxury to interchange compatible upper and lower receivers with ease, often in a matter of minutes and without the necessity of an elaborate toolkit, thus transfiguring the firearm’s capabilities. A rapid switch from a typical 5.56 NATO to a .223 Wylde or .224 Valkyrie is executed with a mere snap of the fingers.
Consequently, one can acquire a complete AR, ready to discharge as soon as it’s verified for function and loaded, and have the option to augment its attributes through a simple swap of the upper in the future.
The AR platform’s modularity affords the owner the possibility of maintaining a solitary lower–frequently the sole unit bearing a serial number and subject to regulation–compatible with a plethora of diversely configured uppers, each earmarked for a distinct application.
In tandem with this, it should be noted that uppers are generally interchangeable across a variety of lowers, a facet contributing to the AR’s reputation as the quintessential “Legos for grown-ups.”
Pushing the envelope further, do-it-yourself enthusiasts and gun-kit assemblers can initiate their project with merely a standalone lower receiver and progressively piece together their ideal firearm by selecting a premier complete upper receiver in line with their desired configuration.
- Best Value Complete Upper
Perched at the pinnacle of economical AR solutions, the experts at Palmetto State Armory have, without a shadow of a doubt, redefined the landscape of the black rifle market with their offerings over the last ten years. Their arsenal, epitomizing the perfect fusion of quality and affordability, is further bolstered by an extensive supply chain that consistently delivers availability, marking a significant triumph in these tumultuous times.
Nestled within their trove of deals, the 16-inch PSA M4 5.56 NATO carbine uppers emerge as a standout, presented in either a 1:7 or 1:8 twist rate. These assemblies arrive decked out with a stalwart Magpul MOE handguard and barrels crafted from robust 4150V chrome moly vanadium steel paired with a featherlight handguard.
In a nod to functionality, they are equipped with a set of sights – the Magpul MBUS being the usual suspects – and come standard with a full-auto profile bolt carrier group, all astonishingly priced at comfortably less than $500.
My personal experience with the 16-inch upper has been threaded into the fabric of my PA-15 usage over the years. This component has reliably executed its duties in ejection, feeding, and overall performance without fail. Indeed, this upper serves as my benchmark for assessing an array of attachments, from tactical lights to sound suppressors. Even with various suppressor configurations tested on it, the PSA upper maintained its composure, never exhibiting undergassing tendencies or signalling distress.
The agility of the upper contributes to an ergonomically pleasing and evenly weighted shooting experience. Although the limited Picatinny rail space atop might constrain the placement of additional gear, it nonetheless yields a rifle ensemble that remains exceptionally user-friendly.
Admittedly, the barrel’s plain CMV steel constitution with a simple birdcage flash suppressor is an exercise in material pragmatism, a strategic choice that underscores PSA’s commitment to delivering superb value. For the AR aficionado seeking either a foundational upper to complete a build or an alternative configuration, PSA’s proposition is unequivocally compelling.
- Best 16″ Upper
Switching gears to the upper echelon of AR expanse, Aero Precision distinguishes itself with a cache of variants ranging from stripped to fully decked-out uppers, each brimming with features. Their persistent claim to fame rests with the M4E1 Enhanced upper, a component redefining handguard integration through its unique free-floating design, fortified with M4 feed ramps and precision T-marks.
- Best Stripped
Shifting the spotlight to Bravo Company Manufacturing, one observes their prolific lineup of upper receiver groups. These span diverse lengths and calibers, from compact 9 and 10.5-inch pistol uppers to the more extended 20-inch rifle configurations. A highlight within their collection is the Kyle Defoor KD4 series uppers with precision SS410 barrels, precisely tuned to harmonize with 77-grain projectiles.
- Premium 16″ Upper
In the realm of premier offerings, Daniel Defense’s Georgia-rooted craftsmanship reigns, evidenced by their extensive selection of top-notch complete receivers. Amongst their arsenal is the MK12, outfitted with a USSOCOM-spec MK12 gas block on a rifle-length system, culminating in a buttery-smooth shooting experience with its 18-inch stainless steel barrel – an assembly that doesn’t just perform, it excels.
- Best Short Barrel Upper
Lastly, with roots stretching into the Keystone State, Geissele Automatics has etched a reputation in the annals of AR-15 uppers, with their Super Duty models commanding respect in the field. When the sought-after SDs prove elusive, the bombproof URGI steps up, replete with Geissele’s hallmark suite of enhancements, from the Super Modular Rail MK 16 handguard to the Airborne charging handle and the Super .750 gas block – a fortification of reliability and performance.
