RE: .003 or .006
I have always bought at least .003 arrows and everyone always told me that for hunting that it would not make any difference. Well, they are full of crap. Even with field tips my groups were not as tight as they were with the straighter arrows. Then add a fixed blade head on the end and there was no consistancy at all with them. Either spend the extra money on straighter carbon arrows or buy alluminum Easton super slams.
I want to add something so that you will understand what those numbers really mean. 6 thousandths of an inch does not sound like much but what that means is that they can vary as much as 6 thousandths of an inch one way and 6 thousandths of an inch in the opposite direction. So you could end up with an arrow that from one end to the other could be out 12 thousandths of an inch total. That's a lot for an arrow to be out. You may as well be shooting cedar arrows.