Since converting my GLOCK 21 to 10mm, I’ve tested a few different types of ammo from it, but the requests just keep coming — everyone wants to see DoubleTap ammo tested in 10mm. The reason is simple — most major manufacturers are selling “watered-down” versions of 10mm ammo. A simple example is Federal’s Hydra Shok. The 10mm version is barely, scarcely any more powerful than the .40 S&W version. According to Federal’s own ratings, the .40 S&W Hydra Shok is rated at 1,000 fps. Their 10mm version is just 1,030 fps. That’s barely over 420 ft/lbs of energy — paltry for what the 10mm is capable of. “Full-power” 10mm loads should be delivering more on the order of about 650 ft/lbs or more . . .