What I have heard and what I do with my AR2078a is this. Take a very small drop of PelGun oil (ie, touch the tube tip to the tip of the cart) and apply it to the nipple of the full CO2 cart before you drop each of the 2 carts into the tube of the gun. This seems to be enough to keep everything properly lubricated. Also, be sure the threads on the CO2 tube are clean and oil those, too. Otherwise, it can be really tough to unscrew sometimes. In a CO2 rifle, if you don't want to pay the $5 for a tiny tube of oil, you can just get yourself some 30-wt, non-detergent motor oil from the local auto parts store and save yourself some money.