Greetings all; I have a 1915 Stevens that is in great condition. there is no rust or pitting on the barrel, but there is a bit of oxidation on the sight. It's minimal. I am hesitant to do anything about it, other than keep it clean. It's my understanding that changing the original condition reduces the value. What are best practices for maintaining collectible rifles? thanks.

merhere,  Oxidation on the sight is not an original condition. I treat my guns like they've been in constant use, since day of manufacture. If they're dirty, I clean them, if they're rusty I remove the rust, if I scratch the stock, I try to touch it up. There's an old saying "when you're selling a gun it's patina, but when you're buying a gun, it's rust" That's my story & I'm sticking to it!!!      ...MIKE...

Something about bluing, which in the early days used to be called "browning" due to the brownish tint, is that the bluing finish is really a very dark hard rust that is tough and durable. 

After the passage of time and neglect, the bluing breaks down toward the softer red rust, forming what we call patina, provided we are on the selling side of the table of course. 

I agree with what most have already told you with one small exception. Do not use steel wool on the rust, use bronze wool. Bronze wool can be purchased from Brownells. The bronze wool will get out the rust without polishing off the bluing. Use it with something like Kroil and go carefully.

40 Rod

Thanks for the tips. I will try the bronze wool first.

With the other guys, no rust or dirt on my guns. That Patina BS is mostly used by dealers or traders working on your selling price. If they want to own "attic condion" fine but no room in my rack for it.

I don't sand or polish out the old finish though just get everything nice and clean.  To preserve light application of good oil on the metal, very light wiped on with a rag,  If the wood is dry some thin oil rubbed in is good, lately I use Watco brand tung oil instead of linseed.  Once clean I give whole gun a rub with paste wax, plain old floor wax. Old leather nothing better than Pecard dressing.

Boats

I nagree with 40_Rod,I use bronze in these cases of minor rust along with Kroil with exceptional results and less harm to barrel finish--Fritz

This is all very helpful. The spot I am referring to is at the top of the front sight cylinder. It was probably scraped along the way.  I called it oxidation instead of all out rust because it is just a color shift from barrel blu to brown. There isn't any "texture" or pitting like an aggressive rust spot.