How does one keep the Moisture/ humidity weight/ volume of your powder stable. I wonder if using a dehumidifier in a container with the lids off the powder jars would make a difference.
That's exactly the opposite of what you want to do. The drier powder gets, the "hotter" it burns.
When Western Powders introduced the first Ramshot rifle powders over 20 years ago, they also built a pressure lab with piezo-electronic testing. They're located in Miles City, Montana which is very dry--and hot in the summer. They eventually discovered they had to build an air-conditioned powder-store/loadomg room with doors and cabinets that were essentially sealed. Otherwise the stored powder dried out and burn-rate increased noticeably.
