Installation Instructions

8
Assembly
Once the receiver bushing is in place, you are ready to install the rest of the piston
kit. The Adams Arms piston system is designed to have a gap built into it between
the striking face of drive rod, and piston key of the carrier.
The spec for this gap is .015 - .025 inches. This gap has multiple important
functional purposes. It allows for a slight amount of heat growth in the drive rod.
If the gap is too small, or too large, the drive rod, and piston key of the carrier can
be damaged and cause malfunctions. Since this gap exists inside of the upper
receiver where it cannot be measure, the gap is measured between the back of
the gas block and the drive rod cup. If you do not have a feeler gauge, you can
measure/estimate the distance using the back edge of the gas block, and shoulder
of the barrel.