Even though Motorhead didn't tell you what you want to hear, listen to him. He is one of the guys that you definitely want to show up when you post a topic like yours. What you seem to be unable to grasp is that the design of your gun does not lend itself to producing 920fps with 18grs without major mods. Open your ports to max, install a reg and tune those 15.89's to 880 or invest in a more powerful regulated rifle.
