The PWS MK114 MOD 2-M is a complete AR-15 upper chambered in .223 Wylde with a 14.5-inch barrel, built by Primary Weapons Systems (PWS) (brand part no. MK1-M2U-223-14-NC). It runs on PWS’s Long Stroke Piston System with a 3-setting adjustable gas block, engineered to reduce fouling and stay reliable even when run suppressed. The .223 Wylde chamber handles both .223 Remington and 5.56 NATO, and PWS backs the barrel with a sub-MOA accuracy guarantee using quality ammunition. A PicLok handguard combines Picatinny and M-LOK mounting in one forend, and a Radian Raptor ambidextrous charging handle rounds out an upper built for both left- and right-handed shooters.

Key Specifications

• Chambered in .223 Wylde, which safely runs both .223 Remington and 5.56 NATO ammunition.
• Barreled at 14.5 inches with a 1:8 twist rate.
• Operates on the PWS Long Stroke Piston System, engineered for reliability and reduced fouling versus a direct-impingement gun.
• Features a 3-setting adjustable gas system to tune reliability across ammunition types and suppressor use.
• Barrel finish is anodized for wear and corrosion resistance.
• Backed by a sub-MOA accuracy guarantee when used with high-grade ammunition.
• The PicLok handguard combines Picatinny rail sections and M-LOK slots on the same forend.
• Includes a Radian Raptor ambidextrous charging handle for smooth operation from either side.
• Muzzle is threaded 1/2-28, though no compensator, brake, or suppressor mount ships with this upper.
• Sold as a complete upper, ready to pin to a compatible AR-15 lower.

Frequently Asked Questions

Does this upper come with a muzzle device installed? No, the muzzle is threaded 1/2-28 for compensators, brakes, or suppressor mounts, but no device ships with this upper.

Is this legal to put on any AR-15 lower? With a 14.5-inch barrel and no permanently attached muzzle device, this upper must be built on a pistol-configured lower (no shoulder stock) or a lower already registered as a Short-Barreled Rifle; mounting it on a standard rifle-configured lower without that registration would create an unregistered NFA firearm. Confirm your lower’s configuration before assembly.

What’s the difference between .223 Wylde and standard .223/5.56 chambers? A .223 Wylde chamber is cut to run both .223 Remington and 5.56 NATO ammunition safely and accurately, splitting the difference between the two SAAMI specs.

Buy the PWS MK114 MOD 2-M Complete Upper

Build a reliable, suppressor-ready AR-15 with the PWS MK114 MOD 2-M complete upper. It ships fast from our Lubbock, Texas gun shop, and our AR15 uppers selection has more AR15 uppers to match your build.