Who made the model 30 ranger 16gauge shotgun?

Rangers are pre-war and it might be a Stevens model 520 ,mfg till late 20's, sold as a Sears "Ranger".

If it has a double hump and a square hole on top of the receiver then it's a 520. I have a Ranger in 16 gauge but I keep hearing that it's a model 30 or 31. Can't nail down the model and the receiver's not marked. It only has a "Ranger" on a horse! Barrel has a "Browning pat." stamp on the left side and "full" for choke.

Excellent shotguns, built like a tank, but frowned upon by collectors. Suits me just fine!