justin, use the grease and wipe it clean after shooting or exposure to grit. Grease does not "attract" grit, but will, as will oil, hold it.

A box here and there of thoughtful heavier loads is not the issue. The steady diet is. Like a car engine, we usually don't run it at full power for very long. Full power is there and has its uses when needed, but not as a steady diet. Heavy target guns are, like some stationary engines, made for full time high output.