Primary Weapons Systems MMK116 MOD 1-M, Upper Receiver, 16.1″ Barrel, Black

Product Description

Primary Weapons Systems MK116 Mod 1 is a complete upper receiver chambered in 7.62x39mm with a 16.1″ barrel. It fits AR-15 pattern lowers, so you pair it with your own lower to build a working rifle. The manufacturer part number is MK1-M1U-762X39-16.

The big difference is the operating system. This upper runs the PWS long stroke piston system with a mid-length gas system and a 3 setting adjustable gas regulator. The upper receiver is a proprietary piston design, forged from T6 7075 and finished in black anodize. The barrel has a 1:8″ twist and carries a PWS muzzle device.

Up front is a free-float M-LOK handguard. Back at the receiver you get a forward assist and a Radian Raptor charging handle. The manufacturer builds this line closer to mil-spec and aims it at both civilian and law enforcement users.

Who it suits

This upper makes sense if you already own an AR-15 pattern lower and want to run 7.62x39mm with a piston action. It also fits builders who want an adjustable gas setting. Make sure your lower and magazines are set up for 7.62x39mm.

M-LOK slots on the handguard take lights, slings, bipod mounts and grips made for that system. Add an optic or iron sights of your choice on the top of the receiver to finish the setup.

Primary Weapons Systems MMK116 MOD 1-M, Upper Receiver, 16.1" Barrel, Black Specifications

What’s in the Box

Radian Raptor (per the manufacturer’s listing).

Fits and Pairs With

• Winchester Ammunition USA, 762×39, 123 Grain, 20 Round Box
• PMC Ammunition Bronze, 762X39, 123 Grain, 20 Round Box
• Prvi Partizan Range Line, 7.62X39, 123 Grain, 15 Round Box
• Winchester Ammunition Super-X, 762×39, 123 Grain, 20 Round Box

Ordering from Western Sport

Order online and it ships straight to your door. Western Sport has been a licensed FFL/SOT dealer since 2007, and everything we sell carries the full manufacturer warranty. Questions before you order? Send us a message.

Frequently Asked Questions

Q: What caliber is the PWS MK116 Mod 1 upper?

A: 7.62x39mm. It has a 16.1" barrel with a 1:8" twist.

Q: Does the PWS MK116 Mod 1 upper fit an AR-15 lower?

A: Yes. It is made for AR-15 pattern lowers. Check that your lower and magazines are set up for 7.62x39mm.

Q: Is the PWS MK116 Mod 1 a piston upper?

A: Yes. It uses the PWS long stroke piston system with a mid-length gas system.

Q: Does the gas system adjust?

A: Yes. It has a 3 setting adjustable gas regulator.

Q: What handguard does the MK116 Mod 1 upper have?

A: A free-float M-LOK handguard. It accepts M-LOK accessories such as lights, slings and grips.

Warranty and Manufacturer

Covered by the Primary Weapons Systems factory warranty; warranty terms come from Primary Weapons Systems.

Additional information