Primary Weapons Systems Expands MOD 2 Line with New MK2 MOD 2 Complete Uppers
Boise, ID (September 24, 2026) – Primary Weapons Systems (PWS) is giving AR owners a simple way to upgrade to its renowned long-stroke piston operating system with the introduction of the MK2 MOD 2 Complete Uppers, available in 16.1-inch and 18-inch .308 WIN configurations. Designed to pair seamlessly with compatible existing lower receivers, the complete uppers provide a suppressor-ready, out-of-the-box solution that delivers the reliability, cleaner operation, and sub-MOA accuracy that define the PWS platform.
Built around a 416R stainless steel barrel chambered in .308 WIN with a 1:10 twist rate, the MK2 MOD 2 Complete Uppers are engineered to stabilize a broad range of bullet weights while providing exceptional accuracy. The 16.1-inch configuration (5.75 lbs) offers a compact, maneuverable option well-suited for hunting, duty, and general-purpose applications, while the 18-inch model (5.9 lbs) delivers increased muzzle velocity and enhanced performance at extended distances. With quality match ammunition, both configurations are backed by the PWS sub-MOA accuracy guarantee. Both are available now with an MSRP of $1,799.95.
For shooters who already have a compatible lower receiver, the MK2 MOD 2 Complete Uppers make it easy to add new capabilities without buying another complete rifle. Swapping uppers is a quick, practical way to adapt a rifle for different uses while saving valuable space in gun safes, range bags, or loadout kits. Whether switching between suppressed and unsuppressed setups or choosing the barrel length that best fits the job, the modular design gives the flexibility to customize rifles without adding unnecessary equipment.
At the heart of each upper is the PWS long-stroke piston operating system featuring a three-position adjustable gas regulator. Engineered from the outset for reliable suppressed and unsuppressed performance, the system vents excess gas forward to minimize receiver fouling, reduce operating temperatures, and improve overall shooter comfort during extended firing sessions. The patent-pending PWS Bore Evacuator enhances suppressor performance by using an expansion chamber and the Venturi effect to redirect excess gas at the muzzle, creating a cleaner, more refined shooting experience.
MK216 MOD2 308
MK218 MOD2 308
Each complete upper features a 7075-T651 forged proprietary MOD 2-M upper receiver with forward assist and is paired with a semi-monolithic, 7-sided free-float M-LOK handguard for increased rigidity and consistent accuracy. The included FRC 3 Port compensator, with its tapered-shoulder design, helps mitigate recoil and flash while remaining compatible with PWS PUB suppressor mounts and other common HUB taper mount adapters. The complete assembly is finished in durable MIL-A-8625 Type III hardcoat anodizing for long-lasting performance in demanding environments.
Each complete upper arrives assembled and ready to install on a compatible lower receiver. This allows shooters to quickly configure a rifle for hunting, duty, precision shooting, or suppressed applications. By pairing multiple complete uppers with an existing lower, owners can expand their firearm’s capabilities while reducing the cost, storage space, and transport requirements associated with maintaining multiple complete rifles. Combined with the proven PWS long-stroke piston operating system, premium components, and sub-MOA accuracy guarantee, the MK2 MOD 2 Complete Uppers provide a versatile solution for shooters seeking dependable performance across a wide range of missions.
For more information about the MK2 MOD 2 Complete Uppers and the complete lineup of Primary Weapons Systems products, visit www.primaryweapons.com.
About Primary Weapons Systems
Primary Weapons Systems, Inc. (PWS) is a federally licensed firearms manufacturer based in Boise, Idaho, specializing in tactical and sporting rifles and accessories. We machine our components in-house on state-of-the-art CNC equipment and source any additional parts from trusted, top-tier partners. As a company of shooters, from machining and assembly to quality control and support, we build products that are both highly functional and visually refined. Our mission is to deliver exceptional quality and customer service to shooters, sportsmen, military, and law enforcement at a fair, competitive price. We value long-term customer relationships and welcome direct feedback by phone or email.
For more information, visit www.primaryweapons.com
