Originally Posted By max229:
I’ve had a handful of e-mails asking how to tell if a used Sig is still in good shape or not. After writing the same e-mail over and over for the last five years, I figured it was time to post my thoughts on what to look at when you’re going to purchase a used Sig Sauer pistol.

The first thing to look at is the frame rails. The rails will tell you everything that you need to know about how well the gun has been taken care of. The following is how the colors of the under side of the frame rails will change as your gun wears.

1. Dull Black – No wear, perfect finish.
2. Shiny Black – Slight wearing in of the pigment in the anodizing, this is normal after around 200 rounds.
3. Dark Gold/Orange – The pigment in the anodizing is starting to wear,this is perfectly normal and not a problem, the metal is stillprotected and your frame is still perfectly viable. Most guns reachthis phase between 2,000 and 4,000 rounds.
4. Bright Gold – The pigment in the anodizing is wearing in. Your frame isstill protected and your gun is still perfectly viable. Most guns reachthis phase and remain static from here on out as long as properlubrication is used.
5. Light Gold – The pigment in your anodizing is wearing through, your frame is still protected, but you should keep an eye on it.
6. Shiny Silver – This is where you need to start to worry. The pigment inthe anodizing is worn through, your frame is still protected, but youneed to monitor your frame rails very closely and make sure they remaingreased thoroughly for the rest of your gun’s life.
7. Dull Silver – You’re screwed. Your anodizing has worn completelythrough in the areas you see dull anodizing. From here on your frame isunprotected and it’s time to buy a new gun. It may still shoot andfunction perfectly, but your frame rails will continue to wear at amuch accelerated rate.

The next thing to look at is the disconnector tab on your trigger bar. That’s the part of the trigger bar that sits up highest in the frame. A factory new trigger bar will have a nice radius across the top, a heavily used one will have a flat worn into it. The best way to check and make sure it’s still functioning correctly is to pull the slide back by one-quarter of an inch and pull the trigger, if the hammer doesn’t try to fall you’re OK.

The next place to look at is the barrel. You will notice the “smileys” on the barrel on the muzzle end. If you run your finger down the barrel and feel a dip, you may want to have the gun looked at by a professional, the slide should not be abrading the barrel enough to remove any metal at all. The presence of a dip in the metal would indicate that your slide has a burr in it.

If you look at the front of the chamber section at the top of the barrel you will see a ledge that steps down just before the tube part of the barrel starts. The ledge there should be at a clear 90 degree angle, any rolling of that sharp corner would indicate a soft barrel or one which hasn’t been lubricated properly.

The slide should also be inspected. The slide lock lever detent on the slide should be looked at for burrs or any rounding on the rear or the notch. A burr sticking out can abrade your thumbs if you shoot a thumbs forward grip. A burr on the slide could indicate a slightly soft slide or that the previous shooter kept their thumb on the slide lock lever. A rounded off notch at the back would indicate an improper heat treat of the slide.

ETA: LINK

Originally Posted By scottrh2:
What would be the point of coating it only to have it wear off again? Is clean and lube not good enough?

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Originally Posted By Viper1357:
Thanks for the information.

I have done or looked at many of these suggestions on used sigs, but the thing I find most often is while all the points you mentioned are covered, I find many used sigs are really loose fitting between the slide and frame rails. Side to side mostly, not up and down so much. Literally to the point of 'rattling' even with light shaking of the gun in hand. Yet the barrel lock up is tight, and all other indicators show it is gtg..

The few I've bought even in this loose condition function reliably, show no more appreciable wear, and hold good groups.. Just wonder why they are so much looser than other used semi auto pistols.. It's apparently more annoying than problematic, but it does 'rattle' me a bit..

Originally Posted By Bronc:
What does the underside portion of the frame rail look like? It is my understanding that this is where the article is pointing out to check.

Originally Posted By cornface:


My 229 looks the same as those two. It's about a year old. Somewhere between 500-1000 rounds through it I would guess?