The story on the 520 was told to me a few years back by a retired NY Trooper.
When Smith sent the evaluation models, before shipping the actual full run, several NYSP members were tasked with running the new guns through the paces.
As told to me, this is not the gospel, mind you, the evaluation was done in Troop G, Loudonville, NY. The major who was in charge couldn't hit a barn if he was standing inside it.
As he was a senior trooper, he raised enough of a stink over the lack of adjustable sights that the order was cancelled.
I have no idea which ammo they used for the testing or many of the other details.
Thought I would pass this on.