Louis Berlin's Q-Jet Launch -

Louis Berlin posted this on the Facebook Model Rocketry Fanatics page:

"Finally got to fly a few rockets.....Tried one of the new quest B4-4 fast jack motors and it catoed......burned a hole thru my Citation Patriot....also had to peel label to get it to fit......the rest went good.....hopefully video soon."







In the picture above, check out the lower left of the body tube - 
Here's Louis' B4-4 Q-Jet after the launch - 

Quest/Aerotech has said they are going to slightly reduce the outside diameter of the engines to better fit 18mm (BT-20 sized) engine mounts.
I've heard one other report of a Q-Jet showing some melting of the casing after a launch. 
It's too early to tell, but reducing the plastic casing (and the wall thickness) may not be a good solution.