Think it needs a dot, vertical forward grip and an A2 flash hider. I stuck an A1 style flash hider I had rolling around in it and it doesn't look right. Also have an ancient aim point red dot for a pistol that's at least 20 years old I'm going to try.
I fired a ruger 5.7 pistol the other day. I put two rounds almost on top of each other at 15' with quick aimed off hand shots. My first 5.7 firing and I liked it.
Yeah the 5.7x28 in a pistol will do that, you can empty the gun as fast as you can and easily stay on target with out even trying.
The P50 with a stock and a no magnification red dot has no problem doing 1 inch groups at 25yd with 40gr ammo.