I have been around antiques, furnisher to weapons my whole life, coming from a family of three generations of antique dealers. We have had many NW guns over the years, considered back in the early 1940's as junk barn guns or cheap squirrel guns by most collectors.
Mt father bought a Sharpe NW Trade Gun in 1939 for $1.25 and had to make payments on it, the gun according to Charley Hanson was one of the best condition NW guns he had seen (rated at 90% NRA Antique condition according to him). I sold this gun a few years ago for $3,500.00 to a collector.
Not bragging - but my family has seen a lot of weapons, depending on your location. The same gun maybe referred to my different names as mentioned, proper names such as the "NW Trade Gun", "North West Tradegun", "North West Trade Gun", "Smoothbore Barn Gun", "Squirrel Gun". and so on. I liked what Curly G. used a "Common Smoothbore".
I like this thread guys, your remarks are great, brings back some good memories, thank you ...