Depends on your barrel. Revenges like all cocker can go very low. A guy ran his at 90psi. My friend tried this and ran it around there. If you have a very stiff main spring and crank in your RVA then you can drop your psi. I dont know how efficient it will be though. I would say running it at about 150 psi would be a good psi to run at. Same with the Excal. Maybe about 10psi higher. They can both go low its just your effciency might suffer.