First off you never...NEVER...pregrind coffee, ground coffee is only good for 30 minutes! after that it begins to go bad! So what do you do when you go camping? One thing you can do is grind it anyway and not worry about the coffee going bad and put it in zip lock baggie and take as much air out of the bag as possible; or buy a small grinder like the Porlex Mini that I have which is very small and suitable for backpacking, or in my case bike touring.