Normal Gas Piston
For operation in “Normal” mode, the Gas Piston should be installed with two groved toward the front end of the barrel. This allows the firearm to use more gas to cycle the firearm.
Suppressed Gas Piston
For operation in the “Suppressed” mode, the Gas Piston should be installed with two grooves toward the back end of the barrel. With one grove over the gas port instead of two, this allows the firearm to use less gas to cycle the firearm.
