Why do you worry about it? Most likely you can't measure either and I'm guessing your gonna judge it with a chronograph? Doesn't make any difference what the pressure of a load is so long as the gun doesn't blow up and your getting results you like. If the gun is reaching 100,000 CUP or PSI either one and doesn't blow up but gives tiny groups, you gonna down load because of pressure you can't even measure in the first place?