Thanks for the links Slamfire. Rather dry reading for an old farm boy turned city slicker.
Your comments about lifting the lid and inspecting each jug of powder on a regular basis makes good sense. In 1 pound jugs in the basement in Colorado (where the relative humidity is usually about 20% or less) it should be good for a year at a time, it seems.
I have wanted to try that old H4895 and may give it go. I have the Hornady book that was used to make the loads 30 years ago, so that data should be a good starting place.