You can adjust the Lug depth, cocking rod, and back block. Is it hissing out of the 3-way? That's normal. It's venting the air from the back of the ram before it sends air to the front of the ram.
Yes, you need to remove the grips on the frame, and look for a hole on the inside of the frame. It adjusts the post travel if you must say. The farther the screw is up, the sear will stop sooner.
You could also look into a Shaft kit and a new frame with trigger stops on it. Or look into a electronic frame.