I have a Falcon FN 19? has a light hunter stock single shot .22? Shoots like a dream. The length of the cylinder is 17.5 inches long including the front fill cap, the serial number is 97514. Thought i would be able to find a list of serial numbers or a web page on how to identify what model is what and the spec of how many shots per charge etc and how to service them when they leak air. Anyone know?