The best cylider pin lube I have found is High Speed/High Temp bearing grease.
It stays put, and does a better job of sealing out fouling than traditional Black Powder lubes. It appears to at least triple the number of rounds that can be fired, before the revolver gets sticky and hard to cock.
As OLDwolf indicated, petroleum based grease does not seem to produce tar as long as it is not in where it is involved in combustion.
Whenever I know the revolver will be carried/fired for an extended period, I use a liberal amount on the innards. It protects the small parts and springs from fouling, so complete disassembly is not required in the field, on days the revolver is fired.
There are synthetic high temp greases intended for use on kiln carts and doors, that I think may be a better choice, but at $50+ per 400 gram tubes, I believe I will stay with the $8 Silicone stuff I now use ?