Following a sport scale project as part of the NRC a couple of years ago to build a gap-staged Nike-Nike-Smoke, I have been looking for 3 stage rocket to build to attempt a 3 stage gap-staged flight. One candidate was the BB XII, now an Estes kit. The kit itself is a little too big, but a smaller scale version would work.
While traveling in France this past spring, on a visit to the Musee de l'Air et de l'Espace, I saw a display round of a Monica II, a French sounding rocket from the 1950s. This stuck me as a good candidate for 3 stage gap-staging. For the past several months I have worked on gathering data and drawing up the rocket.
The resulting drawings are attached. There are undoubtedly errors and omissions. Should you see any please let me know. More information and pictures are available on rocketryforum.com in the scale section under the thread "French Sounding Rocket Monica II".