ORIGINAL: jmbuckhunter
Heat will warp them!
And when they get stopped in a foam target they get pretty hot. The foam actually gets welded to the arrow.Now if an arrow was very hot as it got stopped in a 3D target and hit on a little bit of an angle and started wobbling I could see how it could bend.
Carbon arrows don't bend, (permanantly) they warp as jmbuckhunter pointed out.
And as Roskoe pointed out, I too have had ACC's bend because of the aluminum core.