Re: 300 whisper killing power?
the problem with killing deer with subsonic bullets(i've killed 3 with a subsonic 220gr smk from a whisper) is not the speed it's the bullet selection.
the smk's are like shooting them with field points. i shot all 3 in the vitals, and had 1 go straight down, because i got a fair amount of bone, the other 2 went a little ways, but were recovered.
there are not any great bullets for shooting deer with the subsonic whisper. guys have been trying for a long time. you can do it, but make a good shot, and try and hit some bone.
if you are doing close in deer work a suppressed .44 with a good hollow point would work a lot better.