Mia Culpa. Pouring over my chronograph data and gun info I realize I the first 1-2 shots were not low. Actually is was the last shots of the last string and the tank pressure was too low, hard to focus when having that much fun. My cheap Avenger is now dialed in, shooting 860 fps, does not leak, does not have "regulator creep", has a standard deviation of 2 fps is insanely accurate and is providing loads of fun. Sure glad I didn't spend tons of heard earned money on an air rifle just for a pretty wood stock and braggin rights. Thanks to everyone for their kind words, help and information.