Try the Buffalo Bore 158 +P. They advertise 1000 >fps range and I found them snappy but easy to control. If they are right that puts this in the .357 mag catagory and the 158 +P HP is the best stopper out there (worked for me during my LEO days). Stephen Camp writes a lot about this round (but not the BB) in his "The Shooter's Guide To Airweight J Frames." A must read for anyone carrying a J.