It depends on the head. The rage 3 blade has a pretty big profile even unopened. I have seen others that do as well. If they are pushing 5/8 to 3/4 inches closed then I sure wouldn't assume anything and would shoot them to make sure. If you are talking about a head where the blade is almost totally enclosed then I don't think it would be an issue unless you were real close on your spine and the extra length of the head compared to the field point "could" change your POI but I don't think it would be much. Bottom line is you got to test em'.