MK107 MOD 2-M

PWS Long-Stroke Piston System

The MK1 MOD 2-M Upper operates on the highly acclaimed PWS Long Stroke Piston System, renowned for its reliability and reduced fouling. The inclusion of a 3-setting Adjustable Gas System allows users to fine-tune gas flow, ensuring optimal performance in diverse shooting conditions. This innovative system not only enhances reliability but also provides adaptability to various ammunition types and environmental factors.

Why Use the Long-Stroke Piston System?

Opting for a Primary Weapons Systems gas piston system over a traditional Direct Gas Impingement (DI) system on an AR-15 can be motivated by several advantages, particularly in terms of safety, cleanliness, and performance, especially when considering the use of a suppressor. Here are key reasons why you might want to choose a PWS gas piston system:

Reduced Gas Blowback:

In a piston-operated system, like the one offered by PWS, the gas is not directed back into the upper receiver, minimizing gas blowback towards the shooter’s face. This design enhances the overall shooting experience, particularly for those who prioritize a cleaner and more comfortable shooting environment.

Enhanced Reliability:

The piston system typically provides enhanced reliability, especially in adverse conditions or when the rifle becomes dirty. Since the operating components are not exposed to the combustion gases to the same extent as in a DI system, there’s less chance of fouling affecting the rifle’s function. This can be a critical factor for users who require consistent performance in various environments.

Cooler Operating Temperature:

The piston system tends to keep the operating components cooler than a DI system, as the hot gases are vented away from the action. This can contribute to prolonged barrel and component life, reducing wear and potential heat-related issues during extended firing sessions.

Cleaner Action: PWS gas piston systems contribute to a cleaner overall firearm because the fouling from burnt powder and carbon is not directed into the receiver. This can result in less maintenance and easier cleaning, which is particularly beneficial for users who prefer spending more time shooting than cleaning.

Suppressor Use: When using a suppressor, a piston system is often preferred due to the reduced gas blowback and overall cleaner operation. Suppressors inherently increase backpressure, and a piston system helps mitigate this effect, providing a more pleasant shooting experience and minimizing the risk of gas and debris reaching the shooter’s face.

Adjustable Gas Systems: Many piston systems, including PWS, come with adjustable gas settings. This feature allows users to fine-tune the gas flow to accommodate different ammunition loads, suppressor usage, or adverse environmental conditions. This level of adaptability is valuable for shooters seeking optimal performance under various circumstances.

Ambi Bolt Release

The PWS MOD 2-M Enhanced Bolt Release is accompanied by a right side lever that allows bolt hold open and bolt release operations from either side of the receiver.

Ambi Safety Selector

The Radian Talon Safety selector features ambidextrous control from either side of the receiver. It can also be configured for 90 or 45 degree throw operation.

Ambi Magazine Release

The PWS MOD 2-M lower receiver also features a proprietary magazine release lever on the left side of the receiver in addition to the standard release button traditionally located on the right side. This release lever is positioned for left handed shooters to operate with their trigger finger, but is still very handy for right handed shooters as well.

Pic-LOK® Handguard

Combining both Picatinny and M-LOK into one for mounting accessories, balancing ergonomics and functionality.

Chambered in .300 Blackout, the MK107 MOD 2-M SBR is meticulously designed to offer outstanding accuracy and reliability. This caliber choice allows shooters to seamlessly use .300BLK, providing versatility and accuracy without compromising on performance.

The use of 416 Stainless Steel in the construction of barrels highlights PWS’s commitment to providing top-notch performance. 416 SS is known for its exceptional strength, toughness, and resistance to wear and heat. Our choice of this premium steel demonstrates their dedication to producing barrels that can withstand rigorous use while maintaining accuracy.

It’s worth noting that our commitment to quality extends beyond material selection. The fact that all barrels are manufactured in-house speaks to their meticulous control over the production process. This level of oversight allows us to maintain stringent quality standards, ensuring that each barrel meets our rigid specifications for accuracy, reliability, and overall performance.

Understanding Twist Rate

Twist rate refers to the rate of rotation a barrel imparts to a projectile as it travels through. It’s expressed as a ratio, indicating how many inches the bullet must travel to complete one full rotation. For example, a 1:5 twist rate means the bullet completes one full rotation every 5 inches of barrel travel. Twist rate plays a crucial role in stabilizing the projectile, ensuring it flies accurately and efficiently.

The 1:5 twist rate was selected for this MK107 SBR to create the ideal suppressor host for properly stabilizing heavier projectiles used in subsonic ammunition.

PWS FRC

The PWS FRC compensator is specifically designed to be an effective recoil mitigating and flash suppressing muzzle device, but also compatible with popular HUB suppressor mounts like the PWS PUB, Rearden Atlas, etc. This tapered interface promotes concentricity between suppressor and muzzle device and reduces carbon lockup after prolonged use.

The FRC is available in multiple lengths, thread pitches and barrel shoulder profiles.