Good call! I've thought about that. Could be from a point det or mech time fuse. I just wasn't sure. Its def small so it fits the bill. Normally firing pins don't survive detonation without any blemishes, if at all. At least i wouldnt expect one to... Not sure of the content. Rang up high metal on the CZ 3D. Found around military installation so it has to be from our arsenal either way.