As I walked to and fro among the earth, I became aware of the book "Handloading Ammunition" by J.R. Mattern, originally published in 1926. During the search, I found a few references to HA, mostly of the four classes of loads. IIRC, this book was written by someone that handloaded in the 1890s. Perhaps memory tricks me, but another feeling I got was that Philip Sharpe got material from Mattern, dunno. When I receive the Holy Book, I shall not count to five (that is right out!), nor will I stop at two.
Yes, I did find a somewhat worn copy out east, and thanks to the powers of Capitalism, it will come to my outstretched hands. We are not worthy!