This Product is Build to Order

13.9 Duty Upper

  • 13.9″ 5.56mm 4150CMV BA Barrel
  • Mid-length Gas System
  • Riflespeed RS7533 Gas Control
  • 11.5″ Forward Controls Design Mlok Rail
  • Red Right Hand Mil-Spec Lapped Upper
  • Mil-spec Upper Parts
  • Red Right Hand’s Gunsmith Level Assembly

Muzzle Device MSRP + Gunsmithing Pin/Weld Service

Our 13.9″ Duty upper is an excellent option for our customers seeking the shortest possible barrel length for running a suppressor while maintaining “rifle” status with a Pin and Welded Muzzle device.

The pairing of the 13.9″ with a mid-length gas system and the Riflespeed Gas Control is one super reminiscent of the OG Colt Dissipators in feel. These uppers can be tuned right into where you nearly cancel recoil. Excellent back gassing can be achieved where you don’t get gassed out with a suppressor or just shooting lefty becomes ten fold better. We recommend H2 buffer and Standard weight Carbine Springs (White Springco) for the best balanced results.

Our 13.9″ Duty Upper is available without a pinned muzzle device so the buyer may choose their own and have it pinned by their local gunsmith or utilize the upper on a pistol lower. (ALL NFA RULES APPLY)

*This upper is a “Build to Order” Item. We are a small business and All our Duty Uppers are  custom built to order.  Can be expected to ship 4 to 8 weeks after ordering. (Note: Muzzle Device / Rail Availability can affect lead time) We will keep you posted upon ordering, the customer will be able to contact us anytime to find out status.

Additionally: Other muzzle devices can be Utilized so long as they can make up legal 16″ length requirement for Pin/Weld , reach out to [email protected] before ordering.

Weight 5 lbs


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