16" Piston driven upper in 300 Blackout with a stainless steel Isonite QPQ treated, Button Rifled 1:8 Twist Barrel; a mil-spec receiver, enhanced bolt carrier group and charging handle; Triad30 flash suppressor, and Magpul XT rail panels.
The MK1 series, developed by Primary Weapons Systems, is a significant product improvement for the M4/M16-type carbines and rifles. Utilizing our proven long stroke piston system, it greatly reduces fouling in the action of the weapon making it very reliable.
The product improvements have addressed reliability and performance issues as well as reduced carrier tilt, cam pin wear and carrier bounce.
An innovative hand guard system utilizes a proprietary non-free float system that allows the end user to replace individual rails as needed without removing the barrel, barrel nut or even other rails. This system allows you to attach numerous Picatinny rail-mounted devices such as sights, lights, and laser aiming devices.
The proprietary operating system utilizes an operating rod that is attached to the carrier and a floating head piston that is attached to the operating rod. The MK1 series is built to be a true combat carbine. With no unnecessary gas adjustments and only one moving assembly, this is the most rugged, simple and versatile piston operating system available.
Caliber 300 BLK
Weight 4 lbs 9 oz
Overall Length 25.1"
Barrel Length 16.1"
Barrel Specs Stainless Steel, Isonite QPQ Treated, Button Rifled, 1:8 Twist Barrel
Muzzle Velocity 2315 ft/sec (123gr MC)
Muzzle Energy 1462 ft/lbs
Stainless Steel, Isonite QPQ Treated, Button Rifled, 1:8 Twist Barrel
Enhanced Charging Handle
M il Spec Upper Receiver
PWS Enhanced Bolt Carrier Group
Isonite QPQ Treated Internals
Magpul XT Rail Panels
Triad30 Flash Suppressor