The perps had body armor. How would being able to shoot longer distances with a hand gun have helped?
Any gunfire will cause them to pull back to cover, which reduces their ability to shoot people. A vest doesn't make anyone superman. Even with a vest, you don't want to be shot at with a handgun. At the least, it's quite painful to be shot with substantial handgun rounds, and they can even inflict lethal wounds through and around them. Basically, I'm speaking of suppressive fire.
