I was just going to say the same as Rob, to get a gun to hit the same poi at 10 and 20m you would need impossibly low scope mounts, lower than is physically possible on an FTP! or only have about 3ft/lb.
Your impact points sound normal to me. I have recently had a gauge that held pressure, I could fill the gun and shoot it but the gauge didn't go down as fast as the actual pressure in the rifle so after using 100 bar the gauge showed I had used less but then continued to drop after putting the rifle away until it read correctly were it would stay. I did empty the gun and remove the gauge, I had it in my hand still showing 150 bar which dropped to nothing over about half an hour.
So I would recommend you fill the gun and then monitor it, if it holds it could be a slow gauge like I had that delays showing the correct pressure. if it drops you have a leak.
HFT, for people with only 2 buttucks!
VooDoo TwoTwo The next chapter.