“That didn’t have anything to do with it. A couple of years ago the FBI released its exhaustive multi-year study of sidearms which clearly demonstrated the superiority of the 9. LEO agencies took note.”
No, that FBI report did not say the 9mm was superior. In fact, that report pointed out the 9mm was only better in few and specific circumstances where multiple shots were needed.
The report also determined that the most effective way to use a handgun in a shootout situation was multiple, accurate follow up shots. It found that the idea of superior “stopping power” of the 40 or 45 was a myth and that no handgun has “knock down” ability unless the target is hit in the brain or spinal column. Thus, the ability to put multiple shots on target was essential. This is magnified by the fact their studies showed that even their best shooters miss with 75% of their shots in a shootout. Because of less recoil, the 9 is more effective at putting faster, more accurate follow up shots. That’s the exact reason the thousands of law enforcement agencies state that they have returned to the 9 and well as the US army deciding to stick with the 9.
While analyzing the merits of the 9mm vs. the .40 as I bought my S&W Shield concealed carry weapon, I read that modern 9mm ammo was equal to or, in some instances, slightly superior to standard .40 cal ammo. And especially when using +P ammo in the 9mm. Of course the +P ammo would produce more recoil thereby negating the multiple rounds on target arguement. I settled on the 9mm with hollowpoint ammo for personal protection figuring that in a SHTF scenario 9mm would more likely to be obtainable than the .40 cal.