Quality, mil-spec AR-15 gas blocks and tubes for your custom upper receiver build.
The AR's gas system is the heart of the semiautomatic beast: It's responsible for cycling rounds, ramming the bolt carrier group back and forth, and ejecting spent brass. Installing a proper gas system on your AR is critically important. It'll guarantee you enjoy mild recoil, good accuracy and reliability, and a longer lifespan when it comes to all the parts in your upper receiver and buffer system.
The carbine-length gas system is favored amongst 5.56 and .223 AR builders (and the military itself) because this it guarantees rounds will cycle in the worst possible conditions. We partner with top gunsmiths and major manufacturers to provide low-profile gas blocks and carbine gas tubes that are precisely machined from quality steel and fabricated to mil-spec standards.
Excellent question! Need help picking your gas setup? Pistol-length gas systems are required for all subsonic 300 Blackout builds, and all other AR calibers configured with pistol-length upper receivers. That includes 5.56, .223, 9mm, and others.
Mid-length gas systems work well with 5.56 and .223 setups sporting longer barrels, like an 18" or longer setup. Rifle-length systems are required for most .308, 6.5 Grendel and 6.5 Creedmoor builds.
Want even more info? Read our detailed Guide to AR-15 Gas System.
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