Try weighing a load with a powder scale, and then bake it dry at 250 for a few hours, and weigh it again. the difference in the weight will tell you how much water it lost. You might want to leave it exposed to the air to load up on moisture before you weigh it, as it won't lose any if it's already dry. I'm using a brand called Pearls or something like that. I baked it and put it in some metal cans at the top of my gun safe, with a 'goldenrod' heater at the bottom of the safe. Another thing that will absorb moisture is regular drywall board. I cut rectangles that will fit in the top of an ammo can and then wiegh them, then I write the weight on the top before I bake them. I do them at about 250 for three hours. I'm hoping it will keep my ammo boxes and the boxed ammo inside dry. So far so good. Check the moisture content of the drywall occasionally by weighing them. Has anyone else used this? BTW don't burn the drywall or it will stop absorbing moisture. If you overheat it, it will get crumbly and discolored.
