i've had extremely good results hunting with CPHs and kodiaks at 15fpe-19fpe. they really hit hard and it's dramatic how much more shock they impart than a projectile a couple of grains lighter.
anyhow what's been the collective experience at lower power. from the talk .177 heavies are effective from 10fpe up. i'd like to set up a pistol shooting 700fps for 11.5 fpe.
small caliber joy
half of what you are looking for but at 10+ fpe I've always heard .22 is more efficient.
I'm getting just over 50 full power shots from one catridge with a 14" barrel, HDD and power adjuster.
I've got it dialed up to ~530 fps now, but that can change on a whim. I shoot the heavies almost exclusively in this gun.