Primary Weapon Systems, or PWS, is now offering direct impingement upper receivers for AR-15 rifles. A gas-piston specialist, PWS is bringing its premium standards to conventional uppers.
At a glance these uppers look like most standard PWS upper receivers, which use a proprietary long-stroke piston system inspired by the outstanding AK design, but a peek under the hand guard confirms that these use a standard direct impingement gas system.
These direct impingement uppers bring another change to the table, a new price point. By using the simpler gas system PWS is able to bring the price tag down to just $699, making it a lot easier to lay hands on a PWS upper.
The $699 sticker is a Minimum Advertised Price, or MAP, meaning that real-world prices can be even lower.
Beyond the used of the more common gas system and the new price, these uppers share a lot with PWS’s piston-driven uppers.
They start with a standard flattop upper receiver and fit it with a carbine-length Isonite QPQ-treated barrel. This finish is harder and smoother than chrome giving these uppers an inherent edge in accuracy and durability.
PWS uses MILmil-spec 7075 forged aluminum uppers that are CNC machined to their final form. They then receive a Type III MIL-spec hard anodized finish.
The barrels have a 1-in-8-inch twist rate and a .223 Wylde chamber for the widest possible ammunition compatibility. The .223 Wylde chamber is optimized for both 5.56 NATO and .223 Remington and the 1-in-8-inch twist is the most flexible when it comes to stabilizing projectiles of any weight, although PWS recommends bullets in the 55- to 75-grain range.
The free-floating hand guards also contribute to accuracy. PWS constructs its hand guards from lightweight 6061 aircraft-grade aluminum, which brings the overall weight of these uppers down below 5 pounds. The hand guards are modular and use the KeyMod system and PWS includes Picatinny rail segments for use with non-KeyMod accessories.
PWS is offering three direct impingement uppers, one standard 16-inch carbine upper and two compact 14 1/2-inch uppers.
The shorter 14 1/2-inch uppers come with two options of muzzle devices, either a PWS FSC flash-hiding compensator or PWS Triad, an A2-compatible three-prong flash hider. The muzzle devices are pinned and welded, permanently attached, bringing the overall barrel length up to just over 16 inches. This gives users the benefit of having a 14 1/2-inch barrel without the headache of dealing with the NFA process.
The 14 1/2-inch models have carbine-length gas systems while the 16-inch upper has a mid-length gas system. The 16-inch upper is offered with a removable PWS FSC.
These are being marketed as upper upgrades, turning “the rifle you have into the rifle you want,” and as such they don’t include a bolt carrier group or sights or optics. At these prices no one is complaining.
If you’re looking to save a little coin on a PWS build or simply prefer direct impingement systems over gas piston ARs, you’ll definitely want to put these uppers on your short list. More details and specifications can be found on the Primary Weapon Systems website.