So what are t' odds that all three motors from a pack or E9-6s will CATO?  Pretty good apparently... Rocket got about 30 feet off t' rod then BOOM, nozzle blown out t' back and t' burnin' fuel grain blown out t' front.  shock cord stayed intact but t' motor mount was blown out t' back o' t' rocket with t' motor firmly seated inside and t' body tube suffered significant damage.  Loss.  T' worst part is that I have two more packs o' E9-6s that I bought from t' same vendor at t' same time.  Think I'll have t' write those off.