I have a Scandium alloy S&W 340 PD. During DRY firing, you can see a small spark coming from what looks like the firing pin channel area that shoots out into the empty chamber in the cylinder. Would this be caused by the firing pin striking something or maybe a static discharge between the dis-similar metals? I think the cylinder is made of Titanium and the frame of some kind of Aluminum and Scandium alloy.
If this were a spark of the electro-static type of or a spark of the normal type, could it detonate the cartridges in the other non-shooting chambers? To me, it looks more like a the spark you would get from a flint rather than a static discharge.