.38 spl Buffalo Bore 158 gr LSWCHP gas checked +P fired from a S&W 638 into calibrated gelatin with four layers of denim. I kept the revolver and ammo in a Ziploc baggie submerged in ice water on the trip out to make sure the powder was at a pretty low temperature because of my results with Speer 135 gr +P Gold Dot.
BB calibration: 586.8 fps, 3.4"
Impact velocity: 960.4 fps
Retained weight: 159.6 gr
Max expansion: 0.695"
Min expansion: 0.599"