Many of us have differing views about that, but here is mine. I use the above micron grease on double guns at three places ......... (1) the knuckle, where the forend iron rides against it, (2) the bolting mechanism, whatever type it is, that locks the barrels closed to the receiver, and (3) the hook(s) and hinge pin or trunnions. I feel these three places need grease because I believe it gives a superior lube to surfaces that slide more, have greater load bearing, and don't need the lesser viscosity of oil to prevent slowing the movement. Trigger assemblies and lock mechanisms are places I want very thin oil in order to have as fast a lock time as possible.
Every other moving part gets a very small amount of thin oil. Trigger assemblies get lubed with Breakfree CLP, maybe once a year.
All my best, SRH
