Primary Weapons Systems MK107 Piston Upper (7.75" .223 Wylde Barrel) Primary Weapons Systems MK107 Piston Upper (7.75" .223 Wylde Barrel) Primary Weapons Systems MK107 Piston Upper (7.75" .223 Wylde Barrel) Primary Weapons Systems MK107 Piston Upper (7.75" .223 Wylde Barrel) Primary Weapons Systems MK107 Piston Upper (7.75" .223 Wylde Barrel) Primary Weapons Systems MK107 Piston Upper (7.75" .223 Wylde Barrel) Primary Weapons Systems MK107 Piston Upper (7.75" .223 Wylde Barrel)

Description

MPN: M107UA0B / 2M107UA0B

Features:

  • The PWS MK107 Mod 2 Upper is the shortest available option and was the first firearm developed by PWS. Known as “The Diablo”,
  • PWS pistol-length long-stroke piston system - combines the agility of the AR-15 with the reliability of the AK-47 into a sleek and efficient design
  • Three easy-to-use adjustable gas block settings
  • Full-length Picatinny top rail
  • M-LOK system with PicMod Technology in MK1 MOD 2 models - This allows you to mount any M-LOK attachment anywhere on your rail while being able to mount most Picatinny accessories directly to the recessed Picatinny rail section at the end of the handguard
  • The PWS MK107 is forged upper in MK1 MOD 2 models - Material removed from less structurally important locations for weight reduction
  • Increased carrier mass to extend dwell time and delay unlock
  • Lithium Embedded Salt Nitro-Carburized (FNC LIFE HD) coated barrel and bolt carrier for durability, corrosion resistance, and reduced friction

*This upper receiver assembly has a barrel shorter than 16". This upper is only used on AR pistol lower receivers and NFA-registered Short-Barreled Rifle (SBR) lower receivers. All NFA laws apply!

Specifications:

  • Caliber: 5.56 NATO / .223 Rem.
  • Chamber: .223 Wylde
  • Finish: Type III Class 2 Hardcoat Anodized Finish
  • PWS MK107 Mod 2 Upper Receiver:
    • MK107 MOD 1-M: Forged Flat Top Upper - Made from 7075-T6 Aluminum
    • MK107 MOD 2-M: Forged Lightweight Flat Top Upper (No forward assist) - Made from 7075-T6 Aluminum
  • PWS MK107 Handguard:
    • MK107 MOD 1-M: 7-inch M-LOK Rail System - Made from 6061-T6 Aluminum
    • MK107 MOD 2-M: 7-inch M-LOK Rail System with PicLok Technology - Made from 6061-T6 Aluminum
  • M4 Feed Ramps: Yes
  • Muzzle Device:
    • MK107 MOD 1-M: PWS Triad 556 Flash Suppressor
    • MK107 MOD 2-M: PWS CQB 5.56 Compensator
  • Barrel: 7.75” 1:8 Twist Modify Low-Stress Profile .223 Wylde 41V50 CMV Barrel with FN HD Life Treatment
  • Muzzle Thread Pattern: 1/2"-28
  • Gas Block: PWS Long Stroke Piston System - 3-Position Adjustable Gas Block
  • Gas Length: Pistol-Length
  • Bolt Carrier Group: PWS Long Stroke Piston Bolt Carrier Group
  • Charging Handle: Radian Raptor-LT Ambi Charging Handle
  • Weight:
    • MK107 MOD 1-M: ~3.51 lbs.
    • MK107 MOD 2-M: ~3.63 lbs.
  • PWS MK107 Overall Length:
    • MK107 MOD 1-M: ~16.56"
    • MK1 MOD 2-M: ~16.79"

Compatibility:

  • Any Mil-Spec AR-15 lower receiver

Includes:

  • 1x PWS MK107 Mod 2 Upper with .223 Wylde Barrel
  • 1x PWS Rifle Service Tool

picture of adjustable gas blocks

Details:

When you’re ready to leave behind the wear and reliability issues of traditional gas-operated direct impingement systems, Primary Weapons Systems has the upper assembly for you. Whether you’re building a new weapon from the ground up or just had it with the fussiness of maintaining the upper on your old standby, the PWS MK1 is the long-stroke piston AR upper you’ve been waiting for.

PWS MK107 Diablo

The PWS MK107 is a complete piston AR upper with a 7.75 inch .223 Wylde Barrel designed to marry up to your SBR or pistol lower with minimum hassle. Changing to a PWS MK107 Diablo Mod 2 upper allows you to have the best of both worlds: the ergonomics and flexibility of the AR platform and the super reliability of the AK-47.

Primary Weapons Systems built the MK1 upper on an efficient long-stroke AR piston upper design that creates a single unit by joining a floating piston head and the bolt carrier group with an operating rod. This long-piston AR system outperforms both direct impingement systems and short-stroke piston systems. The PWS MK107 requires less regular user maintenance and runs longer with fewer parts failures than either of the systems before it. A multi-position adjustable gas block allows the operator to properly tune his weapon for his chosen ammunition and accessories package.

The PWS MK107 Upper Is Built To Last

The PWS MK107 features next-generation lithium-embedded salt nitro-carburized treated (FNC LIFE HD) Barrels and Bolt Carrier Groups for ultra-long service life. FNC LIFE treatments don’t just coat steel surfaces like traditional finishes; they alter the outer surface of the piece for a hard-wearing finish that won’t chip or oxidize no matter what you put it through. Reduced Carrier Mass allows the MK1 to run with less chamber pressure, making extraction easier. The PWS MK107 features forged construction, giving it a strength you won’t see in the billet uppers the competition pushes.

There are now two different versions of the PWS MK107 Mod 2 Upper. Traditional, “gotta-have-it-the-way-it’s-always-been” guys will love the PWS Mod1, which includes a forward assist. Meanwhile, the PWS Mod 2 loses a little extra weight by paring down the forged upper where the additional mass isn‘t needed and leaving the forward assist behind. The new PWS uppers also simplify the operation of the adjustable gas block to a three-position selector with positions for all unsuppressed ammunition, lower-powered ammunition with suppression, and suppressed regular and high-powered ammunition.

Whichever PWS MK170 upper you choose, you can count on the strength of performance that only continued evolution can provide. Primary Weapons Systems, Because It’s Time. Shop yours online today from Wing Tactical to get your gear where it needs to be. 

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