Some of those tests show the .357 SIG to have a wider stretch cavity than the vaunted .357 Magnum. Not that I'd want to shot by either on of them As for the much hyped HST. That testing shows the HST to actually fragment, and have a more narrow stretch cavity than the more impressive PDX .357 SIG load, or at least it looks like that to me. I still think the TAC XP is the best bullet on the market. 100% expansion and weight retention. No need to shop for bonded or non-bonded. More than adequate penetration with no worry of the jacket/core will separate. Wanna kill these ads? We can help!