175 Grain Hornaday SUB-X bullets in the 308 using Trail Boss.
I have been working on loads for this bullet with the Bushwhacker 46 suppressor mounted on a Ruger American. I am now at 12 grains of Trail Boss and it is still subsonic on a 65 degree day. If time permits today I will set the ATN night vision scope up for a 50 yard zero and later see what the drop is at 100 yards. I can't see shooting past that distance with a subsonic round.