I had a successful flight with an aerotect 38mm fuel grain and a casing from another manufacturer.

After my first flight I had trouble cleaning out the casing nd used a metal acrewdriver to clean it out. I noticed some damage to the outside of the casing but did not notice any hole.

My next two flights were terrible. The rocket just lifted off about 10 feet and then spun round and round.

Later, when I used a flashlight to reAlly examine the casing I discoered a tiny (less than half a mm) hole in the casing.

Can the presence of that hole explain the flight failures? I haven't had a chnace to fly the rocket agai n, but I have purchased a new casing.