Yes, our suppressors will work with the gas-piston type AR-15's. Although, gas-piston systems do not suppress as well as a direct-impingement operating system. The gas-piston system vents excess gas pressure right at the gas block of the weapon instead of directing it back into the action. Yes this keeps the weapons action cleaner and cooler, the trade off is that hot propellant gasses are now released into the atmosphere faster than if they were allowed to cool and expand in the action. Therefore the gun is not as quiet.