This will be updated later with some details. For now be it known:
DAMN, it's hot and humid out there
Shot some .40-65, some .45-70, and a friend, who recently got a suppressor(Silencerco Hybrid) brought it and his .300 Blackout rifle.
On the latter: he'd found a box of the new Hornady 190-grain Sub-X bullets and some load information. I'll try to get the specifics later, but it being a quiet day(probably because most people were smart enough not to be out in the heat) I was able to set up my Chrony, so we got some readings.
Added: he was using H4198, 10.5, 11.0, and 11.5 grains. Average velocities 927, 1025, and 1103fps. Best group at 100 was with the 11.5 load, about 2". That suppressor was quieted things down nicely, too.
According to a calculator I found at the National Weather Service site, speed of sound was about 1146 at that time/temperature, so all of these were subsonic
On the .40-65, some loads were blah, though part of the problem may have been me: I'd been taking 24" squares of white paper to put on the target stand and then putting the 18" target on that, the contrast making aiming easier for me. I forgot those today. One load that worked quite well was a 300-grain RCBS bullet over 57.0 of Goex 2f powder, this at 200 yards