Originally Posted by
Gadfly
Mission is important is selection as well. Alaska State troopers may face cold, ice, heavy clothing, and large animals. Border Patrol faces sand, dust, 140 degrees in the trunk of the car, no large animals, but long open terrain and lots of vehicles. Chicago PD faces high rise housing, crowded conditions, multi family tenements... Game wardens are all alone, middle of nowhere, and almost everyone they stop has a hunting rifle on them (and is often drunk). Not exactly what NYPD would face. All of those agencies are uniformed and carry in a duty rig.
Now look at FBI or Secret Service. Must be concealed, yet not too small to sacrifice capacity or reliability...
As Todd mentioned about agency size, agency mission and working environment will (or should) drive the testing criteria.
I was told that when Border Patrol ditched the .357 revolver for an auto, they wanted an auto round that balistically equivalent to the old .357 158 grain duty load. So they tested multiple calibers and weights, and settled on the 155 grn JHP at 1250 fps as the closest thing they could get into an auto pistol. They actually did testing on projectile energy and bullet drop at 100 yards. Because in BP training back then, part of the scored qualification course was shot at the 50 yard line, and they practiced (not scored) hitting at 100 yards. The thought was, out in the brush of Arizona, back up is along way off, and you can see for miles, and you may have to engage at that distance. Do you think NYPD cares about that capability? BP also shoots a lot around vehicles. So they wanted something that punched a windshield with authority. That would also be something a highway patrol officer would want. Each agency has a specific mission, and is likely to encounter different threats than other agencies.
So BP/INS defined their mission, selected a round to accomplish their perceived mission, and they tested guns to see if they would run using the round they selected.
Is that the "right" way to test? I cant say. But at least in court, they can show some logic for their selection, other than "well, the chief really liked the way the gun looked".