Alliant's Powder Guides have tables, so the on line manual may have one, the pdf one should have one for sure. But the tables are only starting points. Since you got the average of your drops you got the best info for your loader.
Since 16.0 gr of Unique is the top load listed for 7/8 oz 20 ga load with the components you listed I would use the 24 bushing dropping 15.7 grs on average. Unless the 16.4 gr load is pressure tested it will only be a guess. If you want a load that is faster than 1200 f/s you should go to a slower burning powder, like Hodgdon's Longshot.
Since 16.0 gr of Unique is the top load listed for 7/8 oz 20 ga load with the components you listed I would use the 24 bushing dropping 15.7 grs on average. Unless the 16.4 gr load is pressure tested it will only be a guess. If you want a load that is faster than 1200 f/s you should go to a slower burning powder, like Hodgdon's Longshot.
