Canadian Hunter did you mean 10mm or 40 s&w. Because a 10 MM has almost the same knock down power of a 41 magnum. The 10mm is probally the most powerful AUTO on the market except for the 50 AE and a few weird wildcats. They are a very violent round, much more recoil than a 45 acp. The 40 s&w is a cut down 10mm case with a small pistol primer. The 40s&w is a nice round, and is easily controled. Recoil is not much more than a 9mm but a lot less than a 45 or 10mm.