Found this on the Crosman Site: If you have a CO2 airgun that leaks, put two drops of Crosman Pellgun oil in the cylinder seal area and let the gun sit for two hours. Then, insert a CO2 cylinder and shoot the gun to distribute lubricant to the internal seals. Remove the CO2 cylinder and put the gun aside for three or four days. About 40% of the time, you’ll find that the gun will not leak the next time you use it. If it does, it’s time for new seals.