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Questions & Answers
Would my lower require a buffer tube? Expert Answer

Yes, the Primary Weapons Systems MK109 MOD1-M 9.75-inch Upper Receiver is piston operated but will still require a buffer assembly in order to function.

by Ethan, Gear Expert, December 1, 2022
Does it come with Radian Raptor-LT Ambi Charging Handle and BCG (PWS Long Stroke Piston Bolt Carrier Group)? Expert Answer

Yes, the Primary Weapons Systems MK109 MOD1-M 9.75-inch Upper Receiver includes a BCG and Radian Raptor Ambidextrous Charging Handle.

by Ethan, Gear Expert, November 3, 2022
Customer Reviews
Helpful Positive Review 6/5 Stars! by ColbyJack, Verified Owner, August 20, 2022
Purchased this on backorder. I have been trying for ages, to get my hands on one of these 300 blk uppers to pair with my PWS mk116 .223 Wylde rifle. Optics Planet came through for me where no one else could! It took a couple months, but thats nothing...
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Barrel Length: 9.75 inBarrel Twist Rate: 1-8 Muzzle Device: PWS Triad 30 Finish: Matte Color: Black Condition: New

Code: 2D5-URC-RG35D-MK1-M1U-300BLK-9

MPN: MK1-M1U-300BLK-9

UPC: 811154033451

List: $1,129.95Save $80.00
$1,049.95

Product Info for Primary Weapons Systems MK109 MOD1-M 9.75-inch Upper Receiver

There are plenty of AR15 Upper Receivers on the market, and if you're looking for a pistol upper receiver chambered in .300 AAC Blackout, check out Primary Weapons Systems MK109 MOD1-M. With a 9.75-inch barrel, it is the perfect size for a home defense weapon and a fun range gun, and .300 BLK packs a lot of punch that is satisfying to shoot. Plus, the MK109 MOD1-M comes with the Primary Weapons Systems Triad 30 muzzle device and their long-stroke piston system, so you're ready to roll as soon as you install it on the lower receiver. It even has Picatinny rails and M-LOK attachment points along the handguard, making it the perfect choice if you want to add attachments and optics.image

MK109 MOD 1-M Upper, 9.75in Barrel, .300BLK 3 setting Adjustable Gas Regulator, PWS Long Stroke Piston System

WARNING: California`s Proposition 65

Specifications for Primary Weapons Systems MK109 MOD1-M 9.75-inch Upper Receiver:

Manufacturer: Primary Weapons Systems
Barrel Length: 9.75 in
Barrel Twist Rate: 1-8
Muzzle Device: PWS Triad 30
Finish: Matte
Color: Black
Condition: New
Magazine Included: No

Features of Primary Weapons Systems MK109 MOD1-M 9.75-inch .300 AAC Blackout Upper Receiver:

  • 9.75-inch Barrel
  • PWS Triad 30 Muzzle Device
  • Chambered in .300 BLK
  • Matte Black Finish

Package Contents:

  • Primary Weapons Systems MK109 MOD1-M 9.75in bbl Upper Receiver

Primary Weapons Systems MK109 MOD1-M 9.75-inch Upper Receiver Orderable Models

List of Orderable Models

Primary Weapons Systems MK109 MOD1-M Upper Receiver, 9.75 inch Barrel, 1-8 Twist, Matte, Black, MK1-M1U-300BLK-9 , MPN: MK1-M1U-300BLK-9 , UPC: 811154033451 , Code: 2D5-URC-RG35D-MK1-M1U-300BLK-9
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