Product Details: AR9 Upper Assembly – 5.5″ / 9mm / 1:10 / 160699
➲ Upper Receiver
The foundation of all good AR's is built upon a dependable upper receiver. CBC upper receivers offer best-in-class quality while providing you years of dependable service. Boasting a MIL-SPEC type III hard coat anodized finish and machined from 7075-T6 forged aluminum, this M4 flat-top receiver delivers a lifetime of superior function. You want your AR built upon a solid platform - this receiver gives you the confidence that your AR-15 will function when it counts most.
The barrel is one of the few components that directly affect the accuracy and weight of your build. Designed for corrosion resistance, this barrel will not let you down. This barrel is machined from 4150 Chrome Moly Steel, heat treated to RC 28-32 hardness, and properly stress relieved. This barrel has a nitride finish for increased strength and durability. It is chambered 9mm chamber, with a 1:10 twist rate. This is the perfect barrel for an AR9 build, keeping weight to an absolute minimum, while still offering a significant ballistic advantage.
CBC provides a wide selections of AR-15 upper assemblies in a variety of styles and lengths - all partial AR-15 uppers are assembled with everything less the charging handle and bolt carrier group. Our partial upper assemblies offer quality and performance that will satisfy the most demanding shooter. Better yet, all CBC AR-15 uppers are custom built-to-order enabling us to provide you with the best prices you will find anywhere. The quality of our AR-15 uppers are backed by our Lifetime Warranty - if any CBC upper assembly becomes defective, we will repair or replace it at no charge. Get your AR-15 upper assembly at CBC today and save with free shipping!