Customization:
Our primary goal is to build top quality and stylish CUSTOM parts and kits, so we have added a few more Options for you to consider. IF you would like to see specific brand/style Handguards, or each part (Upper, Lower and HG) to be different colors, then please let us know. We want to provide these builder sets the way you want to receive them which is ready to complete and assemble. Please e-mail us to ask!
Billet AR-9 80% Builder Set includes:
– Built to mil-spec dimensional standards
– CNC Machined from 6061-T6 aluminum
– Ltd lifetime warranty against manufacturer defects
Upper Receiver:
– Sleek/low-weight No-FA slick-side design
– Close in slim-line case deflector
– Accepts standard dust cover, pin and spring
– Billet Upper Receiver Weight = 7.2 oz
Lower Receiver:
– Integral trigger guard for added strength
– Machined Mag-well with wide flare
– Rear lug pocket already machined
– Bolt Catch/Rear Detent holes tapped (Pins incl)
– Accepts Colt AR9 style Magazines (Not Glock)
– Last Round Bolt Hold Open (LRBHO)
– Billet Lower Receiver Weight = 10.7 oz
Handguard/Rail:
– Available in (3) styles and multiple lengths
– 1-1/4 x 18 TPI steel Barrel Nut included
Options:
– AR9 Colt Parts Kit (Feed Ramp, Ejector, Bolt Catch)
– 7075-T6 aluminum (when Available)
– Choice of Selector Engravings or None
– Color matched Buffer Tube
– Ambi Bolt Release
– Black Anodized
– Standard Cerakote colors:
Burnt Bronze, Magpul FDE, Graphite Black, OD Green or Tungsten
Distressed Burnt Bronze, Distressed Magpul FDE or Distressed Gun Metal
– or a Custom Cerakote Color (View Here)
Note: Minor fitment may be needed for coated parts due to variances in coating thickness.
Shipping/Restrictions:
Although not generally restricted, you should refer questions regarding manufacture, NFA Regulations, and individual state regulations to the BATFE or your local authorities, or obtain legal guidance prior to manufacturing.
No FFL Required! This billet Colt style AR-9 80% Builder Set can be securely purchased from our website, and shipped direct to your home or business. (See the Shipping/Returns webpage for updated Shipping Restrictions)

![Billet AR-9 80% Builder Set 9mm [Colt Mags]](https://80lowers.com/wp-content/uploads/2022/02/Billet-AR-9-80-Builder-Set-Colt-type-9mm-Anodized-LH.jpg)
![Billet AR-9 80% Builder Set 9mm [Colt Mags] - Image 2](https://80lowers.com/wp-content/uploads/2022/02/1All-ADR-15-Billet-Handguards.jpg)
![Billet AR-9 80% Builder Set 9mm [Colt Mags] - Image 3](https://80lowers.com/wp-content/uploads/2022/02/1All-ADR-15-LightWeight-Handguards.jpg)
![Billet AR-9 80% Builder Set 9mm [Colt Mags] - Image 4](https://80lowers.com/wp-content/uploads/2021/05/90-Deg-Builder-Set-Cerakote-Colors.jpg)
![Billet AR-9 80% Builder Set 9mm [Colt Mags] - Image 5](https://80lowers.com/wp-content/uploads/2021/05/Distressed-Burnt-Bronze-LightWeight-AR-15-LH.jpg)
![Billet AR-9 80% Builder Set 9mm [Colt Mags] - Image 6](https://80lowers.com/wp-content/uploads/2025/08/Billet-AR-15-Ambidextrous-80-Lower-Receiver-Set-RH.jpg)
![Billet AR-9 80% Builder Set 9mm [Colt Mags] - Image 7](https://80lowers.com/wp-content/uploads/2025/08/AR-9-Colt-Build-Kit.png)
![Billet AR-9 80% Builder Set 9mm [Colt Mags] - Image 8](https://80lowers.com/wp-content/uploads/2018/10/Selectors-Engravings-All-v3.jpg)
Mark C. (verified owner) –
Very nice set. Exactly what i was expecting.
Adam M. (verified owner) –
Loved their 80% Lower/upper combo. One of the best I seen around. It took a little bit to get delivered to me but they kept me informed the whole way through and I didn’t mind. I would definitely use this company again.
Ollie S. –
Very nice set, delivered in a reasonable amount of time. 5 stars for communication. I think the trigger pins/selector switch are about 1mm farther forward than a typical forged receiver, so had some weirdness going on. Be careful when drilling those locations. Otherwise excellent.
-Ollie
Mitchell D. (verified owner) –
The fit between the two receivers is perfect and the machining is excellent. The finish is not that great it scratches pretty easy (anodized black) but I always touch up paint my 80% projects after milling. Customer service is outstanding, the communication between myself and 80lowers was spot on with prompt answers to my questions and very helpful. I highly recommend 80lowers for quality parts and a hassle free experience A+
James G. (verified owner) –
Franklin G. (verified owner) –
Upper & Lower were individually wrapped for shipping great care was taken to ensure no damage
Anonymous (verified owner) –
Love it. Working on it now.