ninemm: Jim March's excellent sticky (posted at the top of this Revolver Forum) is the bible...
http://www.thehighroad.org/showthread.php?t=1430
Rather than go over all the ground he already expertly covers, I'll simply mention that you need to look for the obvious and (at a minimum) briefly hit the following:
1. Is it relatively clean and rust free? Carbon residue from firing doesn't mean a thing, but you'd be rightly concerned if the piece is coated in rust or 20 years worth of dust, dirt, and lint. Judging from the photo, I'd say you will have zero issues.
2. Cycle the action and ensure that it does cock, lock, and drop the hammer without any hangups, excessively gritty feel or unusual mechanical noises. Do this for all six cylinders. Thumb cock the weapon (after clearing it!), pull the trigger, and gently thumb lower the hammer each time. Bad form to repetitiously and rapidly dry fire someone else's weapon.
3. Does the cylinder lock up tightly when the weapon is cocked? It should.
4. Are the grips or sideplate missing any screws? Are they buggered up (possibly indicating someone having done an bubba "action job")?
5. Are there any obvious major damages (dings, marring, or bending) to the crane, front / rear sights, ejector rod, grips, or muzzle crown? In other words, does the weapon look like it got dribbled across a concrete parking lot or was it possibly used as a hammer or impact weapon at some time during its life?
6. When you look at the weapon, be sure and inspect it visually from both sides, from the muzzle, from the rear, from the top, and from the bottom. You can do all this in about 20 seconds. Just look for anything that appears to be out of kilter or damaged. Honest wear on a pistol (especially an easily polished stainless gun) is perfectly normal. It
is used. There will be some fine wear or light scratches to the finish. Don't worry about it.
7. Naturally, look down the muzzle for major pitting or rust. Carbon, leading, or copper appearing buildup (from semi-jacket bullets) is no cause for concern. A simple cleaning will take care of most cosmetic issues. If you have a small bore light, key chain light, or mini-flashlight it can assist in visual inspection, but don't get carried away. You are buying a revolver for a couple hundred bucks...not a collectible Ferrari. If you have no light handy, simply open the cylinder, and use ambient light reflected off a thumbnail to illuminate the bore and cylinders when you eyeball them from the other (muzzle) end.
Evaluating a used handgun is not rocket science and considerably easier than inspecting a used car (or even a used lawnmower or bicycle). If it feels or looks like something is mechanically broken...it probably is. If it doesn't...then everything is probably just fine.
Congrats on finding a very nice revolver!
