strength such auto ignition means can be located at either end of the gas generant grain provided the ignition products thereof are directed against an exposed portion of the igniter strip s preferably as shown in the gas generator of fig8 and 9 the auto ignition means is provided contiguous to the initiation chamber 17 such auto ignition means includes a suitable material 21 having the desired spontaneous combustion property such as suitably selected nitrocellulose provided in a groove in cap 12 encircling squib 13 the auto ignition material 21 is held in place by an overlying screen 22 which permits the ignition products produced by the auto ignition material to pass into the initiation chamber 17 the igniter strips 16 extend past the end of the gas generant grain 15 and into the initiation chamber 17 to provide more extensive contact of the igniter strips with the initiation products provided by activation of either squib 13 or auto ignition material 21 the cap 12 in this embodiment fits in the interior of cylindrical housing 11 and is held in place by swaging the end of housing 11 over the exterior of cap 12 resulting in a swage stake 23 a preload assembly 24 is also provided in this embodiment the preload assembly is formed of a relatively resilient material such as a compressed woven metal or a spring washer in order that it exert a sufficient compressive force on the.