Double tap posts number that are exagerated to boost sales they are usually a bit lower than what they post. Light and fast and foot pounds are not how you measure bullet performance. Select a bullet that will penetrate deep and expand, this will usually be a heaver slower bullet. Foot pounds and shock of impact do not do any significant wounding. Aslo the last thing you want in a self defense round is excessive muzzle blast and flash, it slows you follow up shots and since statics show that you will miss more than you will hit you need to be able to shoot accurately and fast multiple times.