i just add a few drops of secret sauce every tin/500ish shots . FWIU too much oiling will build up in the valve and cause problems . i got my AC F/T setup last year and i'm on the second o-ring . when i put in the 3rd/last one AC supplies in i'm gonna order a some viton o-rings to replace all four of them .http://www.gatewaytoairguns.org/GTA/library/Standard%20O-Ring%20Composite.htm
"Excellent temperature and chemical resistance.Excellent mechanical and physical properties.Low compression set and low gas permeability.Not for use with Acetone, Skydrol, or ethyl Acetate.Basic temperature range: -20 F to +400 F*"better temp. and chemical resistance along with higher temp and mechanical (friction) resistance from all the pumping .each material has it's fans so this is just just my opinion ....... and we all know what those are like . LOL .heres the o-ring sizes if you don't know what they are . . http://www.crosman-air-pistol-owners-forum.com/board/index.php/topic,1288.0/topicseen.htmlWyoMan knows these guns inside and out and he prefers the softer 70D rings for pumpers . it's splitting hairs IMO ..... but the price of o-rings is so cheap going overboard is only pennies difference per o-ring so why not ? here's a good source for 0=rings .http://www.mcmaster.com/#o-rings/=udpwoh