I saw that the fps of the 197 round is around 1,700 fps out of the 5.7 USG pistol, and I was wondering what the effective range is for this round for it to actually stop a threat? Is there some chart that shows "ability to mushroom at various fps"?
*updated 5/19/08 to add that the information was for the pistol
*updated 5/19/08 to add that the information was for the pistol