Re: .308 subs: hunting rounds?
My hunting buddy used a .308 Win. with a suppressor to take a moose this season. The load was 12.5 gr. Trail Boss powder, Hornady .30 cal 220 gr. Round Nose (#3090)bullet, Fed. 210 GMM primer. This load averages 1050 fps (chronographed) from his 18" barrel. Don't know what the energy of the bullet was...head shot only. He planted the bullet in the left ear canal...it exited the right side of the skull halfway between the eye and the ear. Range was 57 yds. (laser ranged after the shot). The moose collapsed at the shot...made no sound. We spent a LOT of time researching and working up this load. It averages just over 1 inch 5 shot groups at 50 yds...drops about 12 inches below POA at 100 yds when sighted 1 inch above POA at 50 yds. We swore an oath to each other to take only head shots, at stationary animals, at no more than 75 yds. When you turn the CNS switch off, there is no need for tracking a blood trail.
A whitetail deer head will be a much smaller target. You might get full penetration on a shoulder shot at reasonable range...that is something you will need to experiment with on test media to determine what your limits will be. If you go the subsonic route, please work your load up carefully; practice diligently; and wait patiently for the perfect opportunity.
ymmv Al