I have 18 different reloading books dating back to the 40's and no two give the same recipe for how much of a powder charge should be used in most cartridges. For the 44 Mag I have one book printed in the early 70's that says
7.5 grn of Unique is minimum and I have a lyman book that says 10g as minimum as you stated.
If you look on the manufacturers website they suggest a max of 11grn so it is kind of hard to believe that the powder is only good from 10-11 grn.
http://www.alliantpowder.com/reloaders/recipedetail.aspx?gtypeid=1&weight=250&shellid=33&bulletid=47
The difference is the way they test pressures from there firearms/chambers at the factory, there is lots of variances.
Love it when people post that this reloading book is more accurate than that reloading book and the flame wars start back and forth. Do a search of "Which reloading book is the best, or do you recommend" and you will see a new thread virtually every week. Sometimes there are three threads going at the same time, lol.
You have to use google search tho because this websites search is by far the worst that I have found on the Internet, love the site other than the search.