Today I fired a total of 4*, D12-5 ESTES rocket engines with a bunch of friends. The first flight was on the commercial ESTES model rocket called 'Mean Machine' and the rocket fired first try. The burn duration was about 2 to 2.5 seconds and the ejection charge fired at the specified time as well, and the parachute deployed nominally. The next flight was for a rocket that I designed and the engine took a few tries to ignite but that was only because I crossed the wires of the e-match. Otherwise, the engine preformed well, the burn time and charge delay both performed nominally like before, but
--> the charge was powerfill enough to tear off the braided nylon mason line from it's anchor and subsequently soften the 3d printed PLA of the fuselage, causing the anchor to self-dissasemble and the nose cone, being very light, to drift with the parachute many hectometers away into the treetops, while the lower stage fell ballistically for us to examine. <--
The third launch was to re-launch the ESTES kit model we recovered and it went perfectly despite the parachute becoming a streamer after it got tangled in a tree on the flight before.
NOTE: the winds were between 3 and 8 mph on the first launch and increased to between 10 and 20mph on the subsequent three launches. Addiitionally, i was using a 6ft by 5mm (3/16'') launch rod I picked up from a hardware store and shoved it in the dirt with the standard exhaust shield that comes with the launch pad set and this worked better than anything else for holding the tall rocket vertical for extended periods of time ready on the pad before launch.
*The fourth launch was us being stupid and tying the engine to the side of some of the debris from the second rocket and sending it so it's not actually useful to include details.