CMMG GAS TUBE KIT RIFLE W/PIN

Description

When a gas-operated AR needs a new or replacement tube, the length of that tube is one of the more consequential decisions in the build. A rifle-length gas system taps propellant gas farther down the barrel than carbine or mid-length arrangements, which means the bolt carrier begins its rearward travel later in the firing cycle — after chamber pressure has dropped further. The practical result is a softer, more gradual recoil impulse compared to shorter gas systems running equivalent ammunition, and less mechanical stress on the bolt carrier group over time.

This kit from CMMG is built for rifle-length gas systems and is made from stainless steel, which holds up to the heat and corrosive byproducts that gas tubes are exposed to every firing cycle. The included roll pin is a small but meaningful detail — it’s the part that locks the tube into the gas block, and losing or damaging it mid-build means a trip to the parts bin before you can proceed. Having it in the kit removes that friction.

Whether you’re replacing a worn tube on an existing rifle, building a new upper from components, or sorting out a reliability issue traced back to a bent or corroded tube, this is a direct-fit part for standard AR-pattern rifle-length configurations. No modification required, no guesswork on compatibility — it goes where any other rifle-length tube goes.