Ok, so I have finally locked down a bullet and a load. This load stabilizes out of my 16", 1:10 twist Ruger GSR. If you try this load out of your rifle, I would suggest that you shoot it without any muzzle devices or suppressors first to verify stability and that the round will exit the gun. I chose to go with the Maker Bullets 200gr subsonic expanding REX bullet. I tested a few different loads until I got to the velocity I wanted while being fairly accurate and stable at 100 yards.
200 Gr Maker REX
10.5 gr Trail Boss
LC Brass with flash holes drilled out to 9/64"
Federal 210 LR primer
Avg 1051 FPS
This load shot extremely well, so I made a block of ballistics gel and moved forward with expansion tests. The Maker Bullet preformed flawlessly, expanding within the first 3-5" of gel and penetrating 15+". This round not only shoots well and expands as promised, it is no louder than a mouse fart when fired through my suppressor. I am verly pleased with the results.