Obtain maximum subsonic and supersonic accuracy with a 300 Blackout AR rifle kit.
Most shooters build 300 Blackout AR pistols, since the .300 AAC Blackout cartridge's subsonic loads can obtain good accuracy with a barrel as short as 10.5". But if you want to enjoy subsonic suppression and maximum supersonic accuracy, it makes perfect sense to invest in a 16"-barreled setup like the kits you see above.
Ballistics testing has shown that when a 125-grain 300 Blackout cartridge is fired from a 16" barrel, it obtains the same amount of energy at 700 meters as a 5.56 NATO cartridge at 500 meters. Most agree with this barrel length, the effective range of the round is increased dramatically. Based on hit probability, the effective range is improved to 460 meters, from less than 300 meters using a pistol-length barrel. With a 16" barrel, your 300 BLK AR is also legally configured a rifle and can utilize a standard buttstock for improved comfort and accuracy.
Yes. Even with a 16" barrel, subsonic 300 BLK loads will retain a muzzle velocity less than 1,125 FPS - that's the transonic sound barrier. Anything below this velocity will provide excellent suppressed sound reduction by avoiding that telltale supersonic "crack" downrange. And with a 16" barrel, you'll obtain maximum gyroscopic stability of those heavy sub loads, affording greater accuracy compared to a shorter barrel.
The upper receiver assembly in your kit ships fully assembled and ready to fire once paired with a functional lower assembly. We include all parts required to build your lower assembly, minus the lower receiver itself. You can utilize a stripped lower purchased from an FFL, or you can fabricate your own receiver from an AR-15 80% lower (restricted in some states)! The 300 Blackout platform uses standard AR-15 parts. Be sure to grab an AR-15 jig to fabricate your lower.
These 300 Blackout rifle kits do not include a stripped lower receiver and no components contained in the kits are considered firearms under federal law. Some states have still banned certain firearm parts and kits like these, and we cannot ship such kits to those states. Check our Shipping & Returns page before ordering to make sure your kit can be shipped.
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