When a Grim Reaper pass through they snap closed when the arrow loosed inertia! It may not have been intintionally designed to do this but it is a part of it's design......

video proof

http://www.youtube.com/watch?v=qZOnwNS_cPw

About a 1:20 into video.

Also this:

http://huntingnet.com/forum/bowhunti...-9-19-doe.html

Distance of over 45 yards. Quatering to me. Complete passthrough. Entrance and exit holes has the "Y" from the blades deploying. When arrow was found the blades were CLOSED.

The Grim Reapers are the only broadheads that I have read enough positive and vitrually no negatives about. I tried them this season after always saying I would NEVER use a mechanical. I LOVE these heads.