hey fatcat, this is not a flame so don't take it as one...
please define "knock down power." i have never seen a round that will knock someone down... that is all movie bs. you can rip someones heart apart with rounds and they still have around 20 seconds of fight in them (thats how long it takes them to bleed out).
when you talk about larger caliber bullets in handguns, it's all about the amount of internal damage they can cause. the idea behind a jhp is to expand and stay inside the body cavity... bouncing around and ripping vital organs apart. why? so someone bleeds to death. the bigger the bullet, the bigger the holes it will rip. no round will actually knock someone down... if it did, you would fall down shooting the gun (physics).
because everyone has a different version of "knock down power," i am just interested in what people have to say...