Toss a good quality, used .357 magnum revolver and this guy is dead on.
I agree with you about the revolver. They’re especially handy for women who may not be as comfortable handling a weapon. If a revolver fails, just pull the trigger again.
On youtube there are a lot of videos showing actual penetration of various calibers. I always shied away from a .357 simple because I was worried about over penetration of the neighbors house.
In one video the 5.56 actually had the least amount of penetration using mock sheetrock walls. It only went through two walls and into the 3rd before the bullet broke up. Even the 12ga with 7shot went through the 3rd wall.
The .45, .357, 12ga 00, and 9mm all went into the 4th wall. They’ve even found where the sheetrock will fill the void in a HP round preventing it from expanding.