The PWS MK216 Upper (brand part no. MK2-M2U-308-16) is a complete AR10-pattern upper chambered in .308 Winchester/7.62 NATO with a 16.1-inch barrel, built around Primary Weapons Systems’ long-stroke piston operating system for shooters who want AK-level reliability in an AR10 platform. Primary Weapons Systems machines the 4140 steel barrel with a 1:10 twist and pairs it with a 3-setting adjustable gas regulator, virtually eliminating carrier tilt compared to a direct-impingement design. The upper ships with an FRC Comp muzzle device, a free-float M-LOK handguard, and a forged black-finished receiver. Among AR10 uppers, this MK216 favors builders who want a proven piston system on a .308-caliber AR10.

Key Specifications

• Chambered in .308 Winchester/7.62 NATO.
• The barrel measures 16.1 inches, made from 4140 steel.
• The rate of twist is 1:10.
• Runs a long-stroke piston operating system with a 3-setting adjustable gas regulator.
• Includes an FRC Comp muzzle device.
• The handguard is a free-float M-LOK design.
• The receiver is forged and finished in black.

Frequently Asked Questions

What operating system does this upper use? A long-stroke piston system with a 3-setting adjustable gas regulator, based on the AK47 piston design.

What caliber is this upper chambered in? .308 Winchester/7.62 NATO, with a 16.1-inch barrel.

Buy the PWS MK216 AR10 Upper

AK-level piston reliability on a .308-caliber AR10 is exactly what this MK216 upper delivers. Order it from our Lubbock, Texas gun shop for fast shipping.