It's winter in Montana and the wind chill is about 25 below zero (F) so it's natural that I stay in and keep warm, or go down to the local tavern and stay warmer. I'd been in reloading all day and had tired of the first option and had decided to exercise the second as soon as I got done with my current batch of handloads for my 308. I was dumping and weighing charges of IMR 4895 and I noticed something occurring that had happened before; I was assembling rounds faster as I got closer to the bottom of the powder supply in the hopper of my measure. I might have dismissed it as merely "hitting a good rhythm" in the past but this time I noticed that it was because all of my charges were, A) somewhat heavier, and B) causing the pointer on the beam to stop at the same point on the scale nearly every time, and darned close when it wasn't. I was trickling less, and always the same amount each time. I could almost do it with my eyes closed and not look at the scale.
So. I stayed in and weighed charges with varying amounts of powder in the hopper. Starting with an amount that rose to 1" above the baffle, I got really accurate charge weights until it ran out with less accuracy as the powder column rose higher than that 1" level.
So what does it mean? Who knows? I only tried it with one powder at one charge weight so it may be something quirky and specific to my reloading arrangement but you never know without trying. I normally keep the powder hopper as full as I can but won't when I'm loading for my 308 anymore.~Muir