I need to take a better look at my chronograph.
"To cut through body armor the .224-inch-diameter SS190 projectile incorporates a cone-shaped steel penetrator sitting atop an aluminum core surrounded by a steel jacket. Velocity of the 5.7x28mm SS190 ball load from a P90 PDW's 10.2-inch barrel is a respectable 2346 fps. Out of a Five-seveN pistol with 4.8-inch barrel it clocks 2133 fps. Despite the high muzzle velocity recoil is approximately 30 percent less than the 9x19mm. This 5.7x28mm load was specifically designed to defeat a NATO CRISAT target (consisting of a 1.6mm titanium plate with 20 Kevlar folds), and it will--even at 200 meters."
Good review on the firearm found at