There are a few cases to consider - there is the case of Ron Hunt. He fell from a ladder and had an 18" auger go into his eye and through his skull. It was a 1.5" diameter auger - so in equivalent hand gun caliber it was three times the width of a .500 S&W Magnum, and more than adequate penetration, pretty good shot placement too - I mean if you can shoot someone in the eye with 1.50 cal round with 18" guaranteed penetration, you sort of expect to kill him. But Ron not only lived but was conscious throughout the ordeal:
http://www.snopes.com/horrors/techno/drillbit.asp
There is also the case of Phineas Gage. Phineas was injured in an accident preparing to lay rail for a railroad. An accidental explosion of a charge he had set blew his tamping iron through his head. The tamping iron was 3 feet 7 inches long and weighed 13 1/2 pounds. It was 1 1/4 inches in diameter at one end and tapered over a distance of about 1-foot to a diameter of 1/4 inch at the other. The tamping iron went in point first under his left cheek bone and completely out through the top of his head, landing about 25 to 30 yards behind him. Phineas was knocked over but may not have lost consciousness even though most of the front part of the left side of his brain was destroyed
Again… if you can shoot someone with 1.25 caliber round and send it clean through his head – you expect to kill him.
According to Evan Marshall and Ed Sanow the 1.50 caliber auger round which reliably penetrates bone and flesh up to 18” has 0% street success. The 1.25 caliber tamping iron round which likewise completely penetrates bone also has a 0% street success rate. Me personally, if I had a choice between shooting someone with a .40 caliber bullet or a 1.25 caliber tamping iron – I’d choose the tamping iron. But that’s just me.
I just think it goes to show that there is no such thing as a “one shot stop”. It was an attempt to measure bullet effectiveness, it wasn’t a bad idea, but those two guys staked their livelihood on it – it became “their thing”. They were making money off the books, speaking etc.. and because of that – even when problems came to light about their methodology or data gathering or validity of their conclusions they had to defend their shtick to the very hilt. I think they started out with good intentions, but they were over their heads scientifically, medically, mathematically and statistically speaking.
I personally think that after looking at issues, it’s just not possible to even qualify in a statistically reliable way - this thing called a “one shot stop”. And for addition reasons, it’s not possible to glean a statistically reliable correlation between this nebulously defined “one shot stop” and “ammo effectiveness” (another nebulous term).
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