The following is an interesting video about why the FBI uses 9mm:
The video is an interview at the FBI's Ballistic Research Facility with Scott, an FBI agent/researcher who has been at the BRF since 2010 and is about the FBI's move to 9mm semiauto.
From what he said, the caliber is not much of a consideration. It is the ammunition that matters.
The discussion on 9 mm starts at 17:20 into the video.
At 19:08, "We can give you more velocity for that caliber and get the bullets t be more consistent through the intervening barriers than the others and ensure functional reliability in the gun across a fleet. ... You are giving us the ability to put better engineering and more engineering into the nine than we can in the others."
At 21:29, "The gains we saw in research were unbelievable for our shooters."
In a test including people who had never held a firearm up to hostage rescue personnel, they comparred a 40 and a 9 in rapid fire: "At the end of all those assessments, six out of ten shooters were faster in their shot strengths and significantly more accurate by just shooting the 9 millimeter pistol over the 40.
At 23:17, "When people talk about shot performance, they always talk about a shot straight at somebody standing in your home, right? Someone's coming up the stairwell at your family and you're going to defend it or you're us out there on the street affecting an arrest. They want to talk about this that I can go to Cabela's up the street here and buy almost anything off the shelf there and I promise you you're going to be just fine right here (pointing at his center of mass). It's when you turn and you've got to drive through the large bones of the shoulder, the other things. Somebody is holding an AK-47 up and you got to drive through the forearm to then get to something that sustains the life functions of that human target, that's when it all changes for us. And it's when those 9 millimeter bullets with their right design and the attendant velocity we can get from it outshine the others in terms of consistency."
The video is an interview at the FBI's Ballistic Research Facility with Scott, an FBI agent/researcher who has been at the BRF since 2010 and is about the FBI's move to 9mm semiauto.
From what he said, the caliber is not much of a consideration. It is the ammunition that matters.
The discussion on 9 mm starts at 17:20 into the video.
At 19:08, "We can give you more velocity for that caliber and get the bullets t be more consistent through the intervening barriers than the others and ensure functional reliability in the gun across a fleet. ... You are giving us the ability to put better engineering and more engineering into the nine than we can in the others."
At 21:29, "The gains we saw in research were unbelievable for our shooters."
In a test including people who had never held a firearm up to hostage rescue personnel, they comparred a 40 and a 9 in rapid fire: "At the end of all those assessments, six out of ten shooters were faster in their shot strengths and significantly more accurate by just shooting the 9 millimeter pistol over the 40.
At 23:17, "When people talk about shot performance, they always talk about a shot straight at somebody standing in your home, right? Someone's coming up the stairwell at your family and you're going to defend it or you're us out there on the street affecting an arrest. They want to talk about this that I can go to Cabela's up the street here and buy almost anything off the shelf there and I promise you you're going to be just fine right here (pointing at his center of mass). It's when you turn and you've got to drive through the large bones of the shoulder, the other things. Somebody is holding an AK-47 up and you got to drive through the forearm to then get to something that sustains the life functions of that human target, that's when it all changes for us. And it's when those 9 millimeter bullets with their right design and the attendant velocity we can get from it outshine the others in terms of consistency."
