The Max may not be the top for your gun. Printed loading data from the manufacturer shows how much powder it took to reach the maximum allowed pressure in the particular gun they were using that day. These figures have mysteriously reduced themselves in the past few years so i have to believe that the world we live in today has most powder manufacturers a little shy because of the many liability lawsuits that are swirling around the court rooms as of late.
I would not wish to see you harm your gun or get hurt and i do not mean in my first paragraph to seem as if i would advise anyone to do something unsafe. The manufacturer of Blue Dot says the top load for a jacketed 180 grain bullet loaded to 1.120 is 8.9 grains. Since jacketed bullets create more pressure for the same amount of powder i would say your lead bullet load of 7.7 for the same weight bullet would be more than safe as long as your OAL is at 1.120 or better. Fire a few test rounds and study your cases for high pressure signs. If none are found you should be fine.