This .30 caliber JSB Hades was shot into 20% ballistics gel at a modest 915 fps for hunting range penetration speeds. The penetration was 7" and it expanded to .370". Seems like the near perfect projectile for medium sized game animals and varmint.
That's been my experience so far. Their terminal effect is doing the job. I'm shooting at around 872fps & MIGHT be getting a better mushroom on the pellets, believe it or not.