Specific things to check on used semi-automatic pistols
1. See that all of the controls work smoothly and with a reasonable amount of pressure. The safety should prevent the gun from firing (check by setting the safety and pulling the trigger normally). The slide lock should hold the slide open. The magazine release should release the magazine easily and yet hold it securely in place until it is pushed. If there is a grip safety the gun should not fire unless the grip safety fully depressed. If there is a magazine safety the gun should not fire unless the magazine is in place. Also, pulling the trigger should not fire the gun when the slide is held slightly out of battery.
2. Cycle an autoloader to verify that it operates smoothly and properly. See that the slide is tight and reasonably free of slop when closed and the pistol is cocked. (There is ordinarily some play or the gun will not function.) Verify that the pistol fieldstrips and reassembles correctly. Also see that the action has been kept reasonably clean for proper functioning.
3. Examine the slide (especially at the front and at the ejection port) and frame for excessive wear or cracks. Aluminum alloy frames are particularly susceptible to developing hairline cracks (and eventually failing) from extended use.
4. The cocked hammer or striker of a SA auto pistol should not drop when the slide is closed smartly. If you can make the hammer drop by letting the slide slam closed the gun is unsafe.
5. Check the magazine(s) for wear and condition. A proper magazine is very important to the functioning of an autoloading pistol. You want the original, name brand, magazine(s) in good condition. Inspect the feed lips for bends, cracks and wear, and insure that the seam at the back of the magazine is tight.
Also check the bottom of the magazine to insure that it has not been ejected from the pistol and allowed to fall to the ground. This looks great on TV or at action matches, but in real life it is very hard on magazines. Magazines are not expendable.
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