This is a simple guide that will cover the basics of what you need to look for in buying a used handgun. Functionality Semi-Auto The first step is to work all of the functions of the gun. Pull the slide back and note how it feels. You are looking for ample resistance from the recoil spring. As the gun increases in caliber it generally will increase in how much resistance the recoil spring offers. If the slide is easy to rack rearwards then it is indicative of a worn recoil spring and a high round count. Work any of the buttons and controls on the gun. The magazine release should be smooth, the slide release should hold the slide back properly (ie. not rounded off), and any external safeties should have good positive feel engaging and disengaging the safety. Pull the trigger and ensure the gun fires, you should hear an audible click as the hammer falls / striker releases (dry firing does not hurt modern guns). After pulling the trigger cycle the gun to ensure that the trigger will reset, this is a common failure for some .22 LR model handguns. Special Note on 1911s - When pulling the slide rearward you should be doing so at a medium pace to get a feel for the timing of the locking lug. If there is considerable effort required in the middle of the process then it's indicative of improper timing and this may cause the gun to have issues. Ask the previous owner if the gun had any trouble feeding. Revolvers It is absolutely vital that you check the functionality on a revolver as improper functionality on a revolver leads to shooter injury more than any other gun. It also requires a bit more know-how to go over the operation on a wheel gun. The first step is to check the functionality of the gun through a firing process. You want to open the cylinder, rotate the cylinder and feel for any un-smooth operation, close the cylinder, and pull the trigger. On certain older revolvers it is not a good idea to dry fire them, specifically older Colt's that have the firing pin attached to the hammer. On modern guns, this will not hurt them. The trigger in double-action should be smooth and linear. When you are cocking the gun into single-action you should feel a smooth, linear pull rearward. If you feel significant resistance as you near the end of pulling the hammer then the gun might have some internal component issues and should be inspected by a gunsmith. The next step is ensuring timing and lock-up. As revolvers age they wear many components that insure that the gun has proper timing, and it is vital to insure that they are in good working order. Close the cylinder and rotate it until it locks. Using your hand push the cylinder forwards (towards the barrel) and rearwards (towards the grip). The movement you are feeling is referred to as cylinder endwalk and should be minimal. Excessive endwalk requires replacement parts that need to be installed by a competant gunsmith. The next item to check is the rotary lock-up of the cylinder. When it is locked-up try to rotate the cylinder (make sure the hammer is down on a single-action cowboy revolver). This play should be very little. If you are at a gun store, compare it to a new model. Particular guns like Rugers and Smith & Wessons tend to have better lock-up than cheaper counterparts. Visual Condition (Wear) Semi-Auto Semi-autos have a number of wear points so a number of wear marks on moving parts is normal. However, if there are large points that are polished and have the finish removed then this is indicative of heavy usage. In extremely hard use conditions the gun will actually develop valleys and ridges where there is metal-on-metal contact. While this doesn't make the gun inaccurate or unsafe, it is letting you know that the gun has had ALOT of rounds through it. Holster wear is generally marks from contact with the holster on the slide and front portion of the frame. The muzzle end of the slide will show the most wear especially on the edges. It is purely cosmetic wear and does not affect the mechanical operation of the gun. Look the gun over for excessive copper shavings and powder residue, generally emulsified into the oil. This usually means the owner was lazy in cleaning the gun. While in the vast majority of the guns on the market this has absolutely no ill-effects, it's just one of the indicators in poor maintenance if you are buying a high round count gun. If it's had less than a thousand rounds through it then I wouldn't worry about it. Some prevalent gun builders actually suggest that the guns be ran dirty during break-in to ensure functionality, and that makes sense as a dirty gun is dirty because it works. Revolvers Wheel guns generally maintain their looks better than most semi-auto handguns due to the concealment of it's moving parts. However, one notable wear point is found on the cylinder about half an inch from the hammer end of the gun. This is from the locking lug riding the cylinder, and is normal for even brand new guns to have this. One thing you really need to look for on wheel guns is pitting. Look around the start and end of the barrel for any pitting that is a result of leaving powder residue on the gun. So many factory .38 SPL loads out there are very bad about coating the front half of the cylinder in spent powder dust. Price At this point you really should have a good idea on price. You've covered the problem areas of the gun and hopefully have come to the conclusion if the asking price is sufficient for the quality of the gun. A competant gunsmith will charge around $50 - 100 / hr. to repair most items, and parts vary widely based upon availability and brand. Finishing a gun costs anywhere from $75 to $400 depending on the amount of finishing (ie. just the slide, or the whole gun), and the type of process used. Traditional bluing and parkerization are generally the cheapest with hard chrome and cerakoting being some of the more expensive processes. Recoil springs are cheap and easy to replace. Cleaning is cheap and easy.