I've recently learned that 5.56mm self defense rounds have a much lower risk of going through my house and then on through the neighbors house, than a 9mm JHP. I'm considering getting a stripped M&P receiver and building a pistol for home defense. I've never shot a modern sporting pistol, so I have no idea about recoil or night time muzzle flash.

I fear the lawyers would hang me if I had to use it for home defense, but the research of over penetration presents a strong case for neighborhood safety.

What are your thoughts on this.