Hi Phil, Mitch ,, I got an answer back from Liam, he basically recommended that if I'm around 860-870 fps with the MK11 heavies that is where I should be, the Regulator is indeed set at factory to 120 bar, some are slightly higher, he said that to try and do anything after this will come at a cost of either shot count, accuracy, or both, As I am not suffering accuracy issues or shot count from what the factory publishes, best let sleeping dogs lay.