Even better, you can re-use your cleaning patches and rinse out your brushes and mops in water.
Even your oiling mop or patches can be washed and rinsed clean if ever necessary.
This makes the cartridge rifles great for long trips away from the home base.
You can make proper oil for the wadding and/or metal preservation out of the fat of pretty much *anything* you kill.
Bear oil is great, but in a pinch I'd be just as comfortable with deer or coon oil to get me through the journey.

cheers
Tinker