Quantity in Stock: RTB Upper Build Kit 16" 5.56 Upper Receiver - FDE | A2 | 13.5" M-LOK | With BCG & CH
This build kit DOES NOT come assembled.
This Complete 16 inch M-LOK upper receiver build kit comes with our RTB 13.5 inch free float handguard and includes only the best Mil-Spec components for your AR15 build. The core components of this kit are a barrel that’s machined from chrome moly vanadium 4150 steel, the RTB lightweight handguard that’s machined from aircraft grade aluminum, an M4 upper that is machined from 7075 T6 forgings, and our black nitride bolt carrier group that is finished with an incredible polish, making the action smooth and easy to keep clean.
As a “do it yourselfers" or DIY enthusiast, you may prefer an AR-15 build kit over a complete upper. Building an AR-15 from a kit allows for a greater level of customization and personalization of the final product. DIYers can choose from a variety of components, such as barrels, handguards, and triggers, to create a rifle that meets their specific needs and preferences. Additionally, building an AR-15 from a kit can be a rewarding and educational experience, as it allows you to gain a deeper understanding of how their firearm functions and how to properly maintain it. Building an AR-15 from a kit may often be more cost-effective than purchasing a complete upper, as it allows DIYers to select only the components they need, rather than paying for pre-assembled parts they may not want or need.
We also carry this Upper Receiver Kit assembled here.
| Barrel | Specifications |
|---|---|
| Caliber | 5.56 |
| Length | 16" |
| Material | 4150 Chrome Moly Vanadium |
| Profile | Government |
| Finish | QPQ Corrosion Resistant |
| Gas System Length | MidLength |
| Gas Block Journal | .750" |
| Dimpled? | No |
| Twist Rate | 1:7 |
| Muzzle Thread | 1/2x28 TPI |
| Weight | 27.2oz |
| Barrel Extension | M4 Feed Ramps |
| Target Crown | 11 Degree |
Bolt Carrier Group:
- Enhanced 9310 Steel (Bolt)
- 8620 Tool Steel (Carrier)
- Bolt is shot Peened and MPI
- All BCG components are pre-polished before being processed and then post polished for an incredible shine
Upper Receiver:
- Machined from a Mil-Spec 7075 T6 forging
- M4 Feed ramps
- Cerakoted in FDE
- Made in the U.S.A.
Handguard:
- MATERIAL: FDE CERAKOTED ALUMINUM HANDGUARD, ALUMINUM BARREL NUT
- PRECISION BORE
- ACCEPTS M-LOK RAIL SECTIONS & ACCESSORIES
- 7075-T6 BARREL NUT
- RAIL LENGTH IS MEASURED ALONG THE TOP
- INNER DIAMETER: 1.36"
Charging Handle:
- Tried and True Standard Charging Handle
- Forged 7075 Aluminum construction
- Mil-Spec Type-III Hardcoat Anodized finish
- Caliber - .223 / 5.56 / 300 Blackout
- Made in the USA
