PWS MK111 MOD 1 Upper Receiver - .223 Wylde, 11.85" Barrel with Triad Muzzle Device

The PWS MK111 MOD 1 upper receiver in .223 Wylde is a compact, purpose-built upper designed for shooters who demand reliability and versatility without compromise. Built around Primary Weapons Systems' proven long-stroke piston system, this 11.85-inch barreled upper delivers the short sight radius and handling characteristics preferred for close-quarters work, hunting in tight terrain, and suppressed shooting. The .223 Wylde chamber accepts both 5.56 NATO and .223 Remington ammunition, giving you flexibility at the range or in the field—and the 1:8 twist rate stabilizes a broad range of bullet weights.

Every component is selected for durability and ease of use. The fully forged upper receiver pairs with a free-float MLOK handguard for accuracy and attachment flexibility. Gas system adjustment across three settings lets you dial in performance whether you're running suppressed, shooting standard loads, or working with various ammunition types. The included Triad556 muzzle device manages recoil and mitigates rise, while the Radian Raptor charging handle offers a proven ergonomic upgrade over standard controls. Forward assist is included for shooters who prefer traditional manual charging options.

This upper strikes the balance that makes it equally at home in a truck gun, a home-defense setup, or a lightweight hunting rig. Whether you're a PWS loyalist or exploring the platform for the first time, the MK111 MOD 1 delivers the no-fuss, high-value performance that's earned the platform respect across law enforcement, military, and civilian shooters alike. Pair it with a compatible lower receiver to complete your build.

Key Features

• PWS long-stroke piston operating system with 3-setting adjustable gas tuning
• Forged upper receiver for durability and mil-spec compatibility
• .223 Wylde chamber accepts both 5.56 NATO and .223 Remington
• Free-float MLOK handguard for modularity and accuracy
• Triad556 compensator included for recoil management
• 1:8 barrel twist rate for consistent bullet stabilization
• Radian Raptor charging handle for smooth, ergonomic operation
• Forward assist integrated into upper receiver
• Compact 11.85-inch barrel optimized for suppressed use and maneuverability

Specifications

Frequently Asked Questions

What's included with the upper receiver?

The PWS MK111 MOD 1 comes with a rifle service tool, PWS sticker, and manual. The Triad556 muzzle device, charging handle, and forward assist are factory-installed and included.

What do I need to complete this upper into a rifle?

This is an upper receiver only. You'll need a compatible lower receiver, bolt carrier group, and charging handle to complete the build. The upper is compatible with standard AR-15 lowers.

Is this upper suitable for suppressed shooting?

Yes. The 11.85-inch barrel length is among the shortest recommended for suppressed use, making this upper ideal for that application. The 3-setting adjustable gas system allows tuning for reliable function with a suppressor installed.

Can I use both 5.56 NATO and .223 Remington ammunition?

Yes. The .223 Wylde chamber is compatible with both 5.56 NATO and .223 Remington ammunition, giving you flexibility with available ammunition.