An air rifle is designed to help a person take care of pesky varmints around his home, and practice marksmanship in his backyard. Air rifles do not get as dirty as real guns, but they must be periodically cleaned to keep them tuned. Cleaning an air rifle is not difficult, because the barrel needs very little attention. Taking the air rifle apart can void the warranty.
Unload the air rifle, and make sure it is uncocked.
Remove the CO2 cartridge from your air rifle. Some air rifles do not require a cartridge.
Place two drops of synthetic oil on a rag. Clean the outside of the barrel.
Clean the inside of the barrel with an air-rifle ramrod and a light degreaser.
Wipe the air rifle down with gun oil. The oil removes current rust, and prevents more from forming.
Do not leave your air rifle outside.