I use them and have had good luck. I have taken 10 animals a mixture
off hogs and deer. The only time I have not had a pass thru was on quatering
away shots on hogs. It slammed intothe opposite elbow and stopped. Even
these only went about 50 yards. I was using a 64# Jennings Rackmaster so I can't
explain your lack of penetration. But I wouldn't blame you for changing heads.
If that happened to me I would drop them too.