We used to run 127 grain +P+ Ranger in our MP5’s at my old department. I liked it because it had a good reputation, plus it was free.
Probably my favorite gun to shoot.
We had a SWAT call-out for a botched gas station robbery/hostage situation at the end of July, just a couple days before I left the department. I had already turned my rifle in, so I dug the MP5 out of my locker and dusted it off. It was a good way to go out.
Did somebody mention +P+ ammo ?