Thanks everyone. I can only surmise that the 7.9 gr. load is somehow incorrect, or overly cautious. I have the Speer manual and is gives a starting load of 9.2 gr. of Bluedot, so I'll probably load several different one starting at about 8.5 gr. and work my way up.
More to come later.
One reason that I take Hodgdons starting loads with a grain of salt.
Always double or tripple check their starting loads, if possible.