Depends on where it’s set from the factory or who you bought it from. Just fill it to 250b and shoot over the chronograph until the speed drops. Record all the shots speed. You’ll need those numbers to see how many shots you get and if your gun needs adjusted. For example, you don’t want the gun to get faster before it drops off the reg. If you don’t have a chronograph, you are just flying blind as a PCP owner.