In the original build I added an ejection baffle. This proved to work too well, and caused D12 motors to eject themselves rather than the parachute. So I drilled out the baffle, and used a Nomex blanket instead to protect the parachute.  But that was too tight, and with the slightly reduced ejection pressure from the remains of the baffle, it became stuck in the tube.  Finally, I threw out the Nomex and used good ol' dog barf.  It worked fine. A lesson here is that better is not always better.