Lighter is Better
The smart thing to do is have the your AR build end up weighing as little as possible, while simultaneously building it with parts that are just as durable as their heavier counterparts. If you can combine these qualities into your AR build, then why wouldn't you? Now, you can even get a lower parts kit with it to jumpstart your next AR build.
James Madison Tactical took one of the lightest AR receivers -- polymer -- and made it lighter still by fabricating the first carbon fiber/polymer hybrid 80% lower. It's super lightweight, yet stronger and more durable than other AR-type polymer 80% lowers. It also comes with its own jig, so all you need is a drill press! The finished receiver will shave those precious ounces off the weight of your workhorse too, so you can have a little more comfort during a long day of shooting.
Polished Lower Parts Kit
Th quality control is second to none and the finish show it: Inside you’ll find a disconnector, hammer hook, and sear that were laser-cut and polished to break as clean as glass at exactly 4.5 pounds. The trigger affords perfect reset after every pull, with no break-in required. Every roll pin presses easily, while the hammer and trigger pins glide in with little effort.
Carbon 50 Polymer 80% Lower Features:
- Weighs just 4.4 ounces when finished
- 20% weight reduction over standard AR lowers
- Stiffer and stronger than many other polymer lowers
- Mil-spec dimensions make the Carbon 50 fit with all other types of mil-spec parts
Complete AR-15 Lower Parts Kit with Pistol Grip
This AR-15 Lower Parts Kit includes all components required for assembling your AR-15 stripped lower receiver:
- Bolt Catch
- Bolt Catch Plunger
- Bolt Catch Roll Pin
- Bolt Catch Spring
- Buffer Retainer
- Buffer Retainer Spring
- Disconnect Spring
- Steel Hammer
- Hammer Pin
- Hammer Spring
- Magazine Catch
- Magazine Catch Button
- Magazine Catch Spring
- Pistol Grip (A2 style)
- Pistol Grip Lock Washer
- Pistol Grip Screw
- Pivot Pin
- Pivot Pin Detent
- Pivot Pin Detent Spring
- Selector Detent
- Selector Detent Spring
- Takedown Pin
- Takedown Pin Detent
- Takedown Pin
- Detent Spring
- SSteel Trigger
- Trigger Guard
- Trigger Guard Roll Pin
- Trigger Pin
- Trigger Spring
Easy-to-Follow Install Instructions
First time assembling, or need assistance with certain steps while installing your lower parts kit? Check out our in-depth instructional and picture guide. It shows the full LPK assembly with tips and tricks, including tools required and the buffer tube and castle nut install.
Need more help or detailed steps? Watch our in-depth instructional video here!
WARNING: Handling firearms parts and accessories can expose you to lead and other petroleum products known to the State of California to cause cancer and reproductive harm. For more information go to: www.P65Warnings.ca.gov
Shipping of various parts and/or accessories are prohibited to states and locales (ie New Jersey, California, New York, etc…) with restrictions against certain parts and/or accessories or "assault weapons" (i.e. states with high-capacity magazine restrictions, manufacturing of semi-automatic weapons, etc..). It is your responsibility to be aware of your local firearms laws before purchasing from our website or machining a firearm. We try our best to keep our shipping page current, but laws change daily.
AR-15lowerreceivers.com only ships within the United States. Federal legislation dictates we cannot ship our products internationally.