I think your last post hit it. Use an AR shooting supersonic ammo. Less over penetration issues. 300 blackout seems like a lot for home defense. Subsonic 300 blackout will go through rail road ties. I wouldn't want to shoot it in the house, terminal performance not withstanding.
I 3 loaded firearms in the house. an AR loaded with 5.56 suppressed, 9mm subsonic, and a 12 gauge. I am building a 300 blackout but i wouldn't use it in that role.
I really want to help you and I will listen to your questions, but my answer will be "get a 6920, a Glock 19, an Arsenal AK, and a Spyderco Delica. Then plant an Aimpoint tree and hope it grows".