Midnight Black 686-3?
 

I just bought a revolver that the seller said was a 586-3 that was mismarked as a 686-3. It is a low sheen blue black color with ser #BBV6xxx. I think it is actually one of the 686Midnight Black guns that were made very briefly but how do I verify that? Also, there are some wear spots in the finish, is there a way to restore the finish? I don't even know how they made that finish except it was some type of chemical process.

I was looking in the SCSW 3rd and it's a little confusing, or maybe it's me. Under the "Variations" section it says these were believed to be manufactured in 1989. But when you look across the page at the "Product Code" section it says 1988.
Your serial number seems to fall right at the end of 1988 or first of 1989 so I believe you may have the midnight black stainless.
You might call S&W and see if they could tell you for sure with that serial number.
I don't know anything about the finish but I'd bet you're going to have a hard time touching it up.

For what it's worth, I have seen a BBV prefix 686-3 that is definitely a Midnight Black gun. Agree with bamabiker that the factory should be able to verify and it may be hard to restore the finish (how do you stain stainless? :) )

My Midnight Black has a serial prefix of BBU, so BBV is very likely a Mid. Black also.

I know for a fact they came out in 1989, because that's the year I joined the Sheriff's Dept., and I bought a Mid. Blk. for my duty revolver. They had just come out, when I ordered it.

If you do a search of the forum here, you'll find a couple threads from about a 6-12 months ago where I posted some pics of mine, after it had rode on duty with me for about 5 years (before we switched to semi-autos).

Found it for you: http://smith-wessonforum.com/s-w-rev...ainless-3.html

I almost hate to mention this, but I bought one of these for my Wife in 1989...A S&W "Gun of the Week" variant. It was a 4" 586, with Hogue Rubber Finger Groove Grips, though I don't recall it being called "Midnight Black" it was still a bead blasted Blue finish...Not Blackened Stainless.... I've been known to make odd mistakes now and then, but this is what I recall.....Zebulon