MSF 13.9” Pin/weld 5.56/.223 Ar15 Rifle Upper assembly



Complete your upper

Add a bolt carrier group and charging handle to complete your upper.


Charging Handle Options

Gas blocking charging handle

Customize your upper

Handguard Options

Muzzle Device Options

Fits Specwar, Saker, Hybrid, Omega, Harvester ASR Mounting System

Gas Block

Foregrip Options

Optic Options

Light Options

Folding Adapter

Lower Parts ?

Ar15 Standard Lower Parts Kit LPK $49.99
Velocity 3lb Enhanced AR-15 Lower Parts Kit LPK $199.00
Ar15 Mil Spec Carbine Buffer Tube Kit $39.99

Custom Dust Cover Engraving

Tools / Extras

Super Duper Extreme Lifetime Warranty

Free replacement 1 time for any not-illegal reason. Shoot it out, stolen, lost, used up, broken, held in evidence in legit self defense, ran over with a truck, lost in a boat, pooped/peed on, herpes, nodes, yeeted, misplaced, eaten by dog, etc, we'll send you another one time. What a deal!!1!1!!!1!!one!1!!

Product price: $379.00
Order total:

Free shipping on all orders over $500

13.9″ Ar-15 5.56/223 Upper (Legal rifle, 16″+)

  • 13.9″ 4150 Chrome Moly (CMV) Barrel. (0.2 longer than 13.7″ for more muzzle device options).
  • 1:7 twist.
  • m4 feed ramps.
  • 556 NATO Chamber (shoots both 5.56 and 223).
  • Mid Length gas system
  • .750 Steel Low Profile Gas Block.
  • Dust cover, Forward Assist installed.
  • Spectre Flash Hider (differs from A2).
  • 12″ Free Float M-Lok Handguard

M16 BCG & Charging Handle available in options. This comes professionally assembled and ready to go. If you order our BCG, we’ll test fire with that one prior to shipping.

  Muzzle device is pinned and welded to make a legal 16″+ upper.  Contact us for any questions regarding this that you may have.


Assembled, Test-Fired, and QC’d In-House

We assemble everything in-house, completely customized to your order. Our engineers have many years of experience in the industry, making sure that everything that goes out the door is built to the highest standard possible.

Prior to shipping, we test fire and follow a strict quality control protocol, paying extra attention to the gas system and headspace, ensuring that your AR-15 will function properly and will reliably fire in all cases. 


High-Quality Components

Over the past 10 years, we have carefully refined the parts we use for our AR-15 uppers. We only use high-quality components in our builds that have been sourced from proven manufacturers and OEMs.

We have built tens of thousands of AR-15s and ensure reliability, durability, and accuracy in all of our products.


Limited Lifetime Warranty

We stand behind our products and have a limited lifetime warranty on the uppers that we sell.  Our warranty protects against defects in product, material, or workmanship.

If there is an issue, simply contact us, and we will handle it. We will repair/replace items if necessary. 

Additional information

Weight 5 lbs
Barrel Size