Alamo, if you want, you can grab a (good) ballistics program (which is it's own conversation) and then feed your data in for your round. You can then adjust the muzzle velocity in the program so that it makes the DOPE match what your actual adjustment was at that 650 yards. With that done, you can throw out the thing you printed from online and you'll have a much more accurate piece of data to shoot with.

That's the cheap way to get a pretty accurate MV if you don't have a chronograph.