craig, here is what i posted for you on LW
you will get many responses on this subject, many will be from people that have never hunted and arrowed elk and many here have. that being said, i have taken my share of elk and would not use anything less than 600gr (my elk rig is 660gr with a 190 gr grizzly). for moose i would go even heavier but this set up would certainly work. while 500gr will get the job done on an elk on a well placed broadside or slightly quartering away shot, there is always the possibility of us not hitting exactly where we were looking. in a situation like that i want that extra momentum. while i have heard many people using 3 and 4 blade heads with success, i like a good sharp cut on contact 2 blade for these big thick skinned animals (although i may try a woodsman head at some time).