in2anity wrote:What's the auditory difference between ~1100fps and ~800fps? Is it a logarithmic or more linear decrease? Is there any actual data out there about this subject?
I haven't seen data, though I'm sure it exists. Go outside and fire a CCI Std Vel 40gn at 1080fps and a CCI Quiet 40gn at 710fps, the difference is significant. The CCI SV has 1gn of powder, I haven't opened a Quiet to measure it. It is probably a lower charge, but it could just be a different powder.
But I think there is some increase in noise when using larger charges to push heavier bullets, while still staying subsonic. I would have to actually measure the reports to be definitive. But they are still significantly quieter than even a .22LR going over 1200fps in my opinion, the sonic crack is very loud. I want to play with loading subsonic shotgun loads one day, a subsonic 450gn+ load should be getting significantly louder than a 40gn bullet at the same velocity, based on my experience, but would it approach the level of a sonic crack?