rodbilyeu, Tell us the serial number and we can tell you a lot more about the gun, however it sounds to me from what you have posted that the gun is probably a police riot gun configuration of one of the various S&W pump shotgun models. It must have some kind of mark or stamping on it to make you believe it was made by Smith & Wesson, right? If so, what was it? Absence of the S&W logo, or it's presence, is often a matter of happenstance and not a clue as to the gun's maker. Riot type S&W shotguns, made under a military contract, are something collectors have been trying to authenticate for years. I've seen two fakes that sold at very high prices, at a Rock Island auction, to unsuspecting buyers. Factory shipping records do not record any military shotgun orders, however it may be that these records were sealed by the military, for whatever reason, and not included in the shipping logs. We need much more info about your gun to pin down it's origin. Ed.