MotorKote makes a moly grease that is slicker than anything I have ever used. It is weird, like krater grease but way more refined. It is sticky, thin looking on your fingertips, kinda like snot. I have been playing with it anywhere I use Aero Shell grease and the results are phenomenal. I put my last lower together using in in a syringe to grease the take down pin detects, trigger pins, trigger, bolt stop, safety detent and buffer detent. It is just viscous enough to allow it to be used in a syringe, but still provides plenty of wear and heat protection to use in boat trailer wheel bearings.
The upper I still assemble with anti-seize.