I clacked many a Clacker!......................
Had the Clacker, had the Nichols derringer belt buckle, but I discount the cap claim as you put a round sticker cap on the back of the spring loaded cartridge into which you stuffed a plastic bullet, so there was no large roll of caps to catch fire and burn, eschewed lawn darts because I saw the danger and refused the entreaties of my kids to buy them.
Do you remember the original slate grey Superball? If you could throw one hard enough against concrete theyd explode, sending Superball shrapnel everywhere! Pulled from the market until the formula was changed to avoid it.