Some lubricant oils and greases contain solid friction reducing ingredients such as teflon powder, molybdenum disulfide, or graphite. Proprietary organic lubricants are becoming more commonly used to boost the performance of existing compounds. Most lube oils are slipperly enough for paintgun applications, however, viscosity should be considered next. The primary purpose of the lubricant is to reduce friction and minimize wear by separating the lubricated surfaces with a thin film. This has to be done without imposing unnecessary viscous drag.
Viscosity is a measure of a lubricant's resistance to flow.
As temperature increases, viscosity decreases. Because of this the opposite is also true. Therefore, when you are selecting a lubricant for your paintgun, you must remember that CO2 is -54 deg. C in liquid state. A lube oil that is the consistancy of motor oil at room temperature, may become so thick during use in the paintgun, that it stops functioning due to viscous drag.