@lehighline I believe you're correct. I think pipe schedule is related to pressure rating. But I haven't had to know any of this stuff in a long time.
I might go with a rotating spring instead of an auger now that you mention it. We use springs as augers at work and it gets the job done.
I haven't had much time to get in the basement and move some coal. The weather has been mild lately so I've been outside landscaping, putting trim on shed, etc, etc. I'll probably update the main layout thread I have when I do find out just how the sand is performing. I also intend to post about the unloader when I get it working better.