This video outlines the essential process of degreasing and properly lubricating a spring-powered air rifle, whether it's new or used. The primary reason for this maintenance is that factory-applied greases often prioritize corrosion protection during storage over optimal performance in use, and secondhand rifles have unknown lubricants. The procedure involves disassembling the rifle, specifically removing and cleaning the piston and the crucial compression tube using a degreaser like aerosol brake cleaner. The most important aspect of relubrication is the exclusive use of Molybdenum (Moly) based greases, as other common lubricants like oil, silicone, or red rubber grease can damage the rifle or lead to performance issues such as "dieseling" or moisture absorption. Proper application involves a small amount of moly grease on the spring and a thin, even layer rubbed into the piston, with attention paid to other metal-on-metal contact points for enhanced performance and longevity.

Very good overview of the elements of tuning an airgun rifle.