Okay, I just have to star with saying that I didn't buy this stuff. I found it in a buddy's garage. I'm pretty sure you have to shout when you say EXTREME SHOCK!!!1!!! Fired from a Springfield GI model 1911 through four layers of denim.
BB calibration: 586.8 fps, 3.4"
Impact velocity: 1,201 fps
"Retained weight": 5.6gr
Those last two figures are approximate because as you can see, the round completely fragmented and I simply weighed the jacket fragment you see in the pic. The round black thing was a polymer plug that stopped at about 4" or so.