ORIGINAL: zak123
I thought you gained KE byshooting a heavier arrow.
True zak,but ponder this.....
Recommended standards: It has been offered by some experts that 45 ft-lb of arrow energy is a good minimum for whitetail deer, while 55 ft-lb is a proper minimum for elk and caribou. It has been further suggested by several in the broadhead business that an extra 10 ft-lb should be added to each of these minimums when mechanical broadheads are used. These, of course, are only rough guidelines. Many animals have been taken through the years, and will continue to be, with well-placed arrows carrying much less energy.
or this.....
SOME PERSPECTIVE:
It should be noted that a properly placed arrow - impacting with 50 ft-lbs of KE would easily generate a clean pass-thru on large game like Whitetail Deer or Elk (as in our experiment with the Patriot above). So with respect to kinetic energy and big-game hunting, there really is no practical difference between the 300 grain arrow impacting with 50 ft-lbs of KE and a 600 grain arrow impacting with 54 ft-lbs. Either would make a clean harvest on big game. So in most cases, the effective difference would really be how far the arrow sticks in the dirt after passing through the animal.
If you shoot a modern compound bow with at least 55# of draw weight, we suggest you not split too many hairs over the issue of KE. If you do your job and place the shot properly, you'll have plenty of KE to make a quick humane harvest. If you shoot mechanical broadheads, or you hunt "thick-skinned" animals like hogs, bear, or buffalo, some additional Kinetic Energy may be in order.
My bow is making enough KE to kill a caribou with a mechanical head.I'm hunting whitetails.So if my bow is already quiet,and I'm already slamming through deer.Why do I need to shoot those big logs?IMO too much emphasis is put on shooting 540gr arrows.I like speed,and speed kills.BUT you have to have a sharp,quality broadhead,or it will become a problem.Those heavy logs do drive those poor quality heads through,but you wouldn't need all that ke if you had just been using a sharp head in the first place.
http://www.huntersfriend.com/arrowhelp/arrow-selection-5.htm