Do not forget for a bullet to go "though and through" it has to penetrate the skin twice. So per your 4" per skin penetration equivalent 2 x 4= 8" and your 11" (19" total need to penetrate) thickness would seem to indicate the bullet would lodge under the skin on the far side (maybe).
I was at a crime scene where a bullet fell out of the victim's shirt while the EMS personnel were working on him. I think the bullet penetrated his T-shirt, then his torso and came to rest inside of his shirt.
Thanks for posting this.
NRA Life Member - Orange Gunsite Member - NRA Certified Pistol Instructor
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