Subs in a .308 better to go heavy or in 175 range

[Aimsmall55]

i recently got a SAS Arbiter suppressor for my .300 blackout, AR-15’s , .300 Winchester mag , and .308 Winchester.
Now ive been experimenting with subsonic rounds in my .308 using trailboss , 178 amaxs, 208 amaxs, and 175 smks.
The rifle specs are as follows: a Stiller tac 30 action , a Bartlein HV 1:11.25 twist at 28” with a Bushnell XRS all sitting in an AICS.
Now from what I’ve read , you want the case volume to be as full as possible so the powder isn’t “loose”.
That being said all rounds have shot good and have been amazingly quiet but I do seem to be getting some vertical deviation with all the loads.
What do you guys recommend doing and what bullet do you think would work best for killing deer inside 100 yards?

 

[cav has been]

I write this as a relative novice subsonic chooter. I had little romance with the A-maxes as they wouldn't stabilize in my 1:12 twist. Taking a clue from the more experienced, I shot some 180 Sierra round noses with fair success. Gunfighter here on the "hide" pointed me at the cast bullets which I have learned to delight in shooting. 164 and 194 gr. cast projectiles are both generally minute of angle or less, certainly way sub minute of deer.
The existing sub. thread here has a wealth of info.

 

[fdkay]

If you want to shoot subs, use your blackout.
Heavy bullets travelling very slowly need a fast twist.
With a 11.25 twist, you'll need flat base round nose projectiles and 180 grainers may still be too heavy, you may have to go all the way down to 150, so what would be the point?
There is a reason blackouts come with around 1-8 twist barrels.

 

[Pesekcw]

^^^^^^^^^^^^^^^^^^^^^ This, been working your same problem, used A-5744 got decent results, but I have better luck with my blackout .75-1 MOA easy, cant duplicate that with the 308 at all. Tried all the way from 165-212 nosler and amax. Buf if you ever find one that works i would love to know

 

[Mullhead]

Been working on my sub loads as well . Always used TB . 10.5-11 gr and 200 SMK . 2.800" shot this group yesterday . 10.7grs remember with subs start high and work low.

 

[NukeMMC]

The heavier the better. Then you have more downrange energy. Using a bullet designed to maximize its supersonic performance may not prove to be as beneficial as it may seem. Some folks are getting outstanding results with spitzer or round-nose flat-base bullets.

 

[roggom]

+1 ^^ flat base bullets do well with subs, so if you have some old hunting bullets give them a go (as far as accuracy).

 

[Str8shot]

Please remember that if hunting with subsonics then you are essentially using a 45acp to hunt deer. Muzzle velocity is around 1050 FPS and 450ft lbs energy.
This is at the muzzle. At 50 yards its even worse.
Is this really the way to make a humane ethical kill?
Don't get me wrong. I love lobbing subs from 50 to 200 yards. But I take pride that In 40 years I have never lost a white tail when using a firearm. Shot placement and proper caliber choice for your intended animal.. It matters.
At least to me.