You also want to store the flare projector in the "Cocked" position, if you screw a flare into the projector while it is in the "Fired" position (which you show in the picture), the flare will fire....

I was a P-3 Aircrewman as well, we got to fire the Flare Projector in training, SERE (Survival, Evasion, Resistance and Escape) School in California. One of my instructors in SERE School shot flares at every jackrabbit he saw, he finally hit one and the flare just bounced off the rabbit, so they are probably not a good defensive weapon.