All I use in my .270 is BST's and they have worked like a champ. As far as "knock down power" I dropped a 400+ pound black bear in it's tracks with a double lung shot. I also dropped 2 whitetail where they stood with the same shot. None of the three had a spinal hit or broken shoulders, simply no lungs left at all. Bigbulls, I understand what you are saying about the small size of the bullett not having knockdown power, but I think you need to take more into consideration than that. For instance, these shells are made to fragment so I think that plays a larger role than the kinetic energy. I could shoot a fmj with 2500 foot pounds and have it pass right through and not find the animal for hundreds of yards. However I could make the same shot with a 1500 foot pounds BST and the animal could drop where it stood simply from the internal damage caused by fragmentation which seems to be the case with this particular round. So I think that there are more things that need to be taken into consideration when referring to knock down power. IMHO. From what I have seen in the field these rounds do a tremendous job and I will never shoot anything else through my .270