Even though I am level 3 and made dozens of launches over many years almost all of my experience has been with Public Missiles that use piston deployment. My avionics experience is also with the Public Missiles design that includes their own BP holders. I am planning now to build a Madcow Rocketry fiberglass kit and need some advice on the deployment. I have both a Missile Works and Perfectflite computer than I can use but am not sure of a design for holding and igniting the BP. I've seen online the Blastcap http://www.blastcaprocketry.com/index.html and Pratt Hobbies ejection canisters http://www.pratthobbies.com/ejection_canisters.htm Any advice about these or other systems would be appreciated . Hope you all had some successful launches at Roc Stock. Bob Brown http://us.imdb.com/name/nm0113141/ http://www.tripoli.org/ #9186-L3 -- ROC-Chat mailing list roc-chat@xxxxxxxxxxxxx //www.freelists.org/list/roc-chat