This single shot .22 cal derringer reminds me of a Remington Rider. BUT.. NO MARKINGS ANYWHERE. I suspect it's a Belgian copy. Straight through bore of 22 cal is dark and pitted, evidence of black powder cartridges. Cocking it is a strange, the motion is more DOWN than back, spring is very strong. In FACT, I can't fathom how a round would stay in place. 22 short falls out, 22 LR fits a little better. Don't worry I didn't fire it. Traces of nickel plate on sides and back strap suggest it was fully plated. Ideas?