Can't say what bullet and weight works best, I guess you could argue that the M9 was designed for 115 gr FMJ since that was the standard back in the 1980s.
However, the standard current military issue we use, M882 (A363/AA49), is a 124 gr FMJ @ 1230 fps. When the M9 first came out, a 115 gr FMJ at the same velocity was the standard (also designated M882). A 124 gr JHP is also currently designated (A260) which is loaded to 1120 fps (but it was a restricted issue item when I was in Iraq). It was not unusual to have 9mm with commercial headstamps versus the military headstamps we were used to.
Based on Alliant's reloading data, your 8.7 of Blue Dot is above max for either a 115 or 125 gr pill but their pressure reading is below the SAAMI spec. Additionally, SAAMI says don't use 9mm NATO (military) in 9mm (parabellum) just like you're not supposed to fire 5.56 in a .223.
Here's a link that claims the military equivalents 124 FMJ M882 using Blue Dot.
http://www.frfrogspad.com/miscellq.htm