for a "normal" rifle trigger or an after market like a timney I use the brake cleaner (if your trigger is plated this will eat off the plating) or just compressed air. To lubricate I either use a good teflon spray or graphite. Always make sure to inspect your weapons before going to the range or out in the field. this will help to alleviate a lot of the "oh sh!!!" when you get out to the range or on the opening day of the season and realize you have a problem with the weapon.
Lifetime member VFW and NRA
"Quando Omni Flunkus Moritati" (when all else fails play dead) -Red Green