Talking about a "Magsafe" Pre-Fragmented round from a S&W m-25.
Rated @ 1,700fps from a 6-inch tube. I was thinking at least 1,300fps, from a 4-incher, and able to frag as claimed.
Most of my testing was done years ago, with 9mm loads. Not sure what to tell someone today, with a big-bor blaster.