[MikePGS]

What exactly do the numbers after the hyphen indicate? like 686-5 or what not.

[hexidismal]

The numbers refer to revisions made in the manufacturing. What they refer to specifically is completely dependent on the revision number as it refers to that specific model.

Using your example of the 686-5 .. heres a quote from my own post #325 back in 2007 in the "The 686" Thread.

The dash numbers are manufacturing revisions in S&W revolvers. Its not just 686s, all S&W revolvers have them. What each revision means is entirely dependent on the model. Sometimes it implies small changes, and in other cases somewhat big ones. For example the 686-5 revision is the last model to not have the key lock.
686 ''dash nothing'' - 1980
686-1, 1986 - radius stud package and floating hand
686-M - 1987 recall stamping on earlier versions
686-2, 1987, hammer nose change, bushing and ass'd parts
686-3, 1988, new yoke retention system, 1990 - 2 1/2" barrel introduced.
686-4 1994 - 1998 - many changes including move to 7 shot, sight changes etc.
686-5 revision built with MIM parts and frame-mounted firing pin. varied other changes
686-6 introduction of S&W internal lock

[Oro]

Here is a source for most revision numbers up to 1980. I do not know of an online source for ones after that; only the reference books.

http://www.handloads.com/misc/Smith.Model.Changes.asp

[dennythetech]

Hexidismal answered for the 686-5, and the 'what not' (especially for older models) can be answered here:

http://www.handloads.com/misc/Smith.Model.Changes.asp

[dennythetech]

Sorry for the echo. I didn't see Oro's post until after I hit the submit button. Maybe my PC is running slow....