In all this of course, I've done careful checkouts of the guns I've been buying... well, except the $40 Remington Mosin 1918... 'cuz it's a $40 mosin, who cares if it's buggered right?
This begs the question, when should you walk away from a gun? Not on price, but on condition? What are you looking for that says "no, sorry"?
I wrote a very extensive (some say too much so), auto-pistol checkout procedure here a couple years ago, but like I said, it's VERY extensive, and it takes an expert a good solid 15 or more minutes to run. Most people don't want to do that, and most sellers probably wouldn't want them to.
So, lets say you're just going to hit a gun show, or a pawn shop, and you want to know the danger signs.
Here's the top ten of what you DON'T want to see in an auto pistols, in order of seriousness (and reverse order of ease of repair). We'll use a 1911 as a specific example, but most centerfire auto pistols are similar:
- Frame or slide cracks, galling, peening, or more than very light corrosion. Pay special attention to the rails (especially around the slidestop cutout and slidestop notch), the breech face, the recoil spring shroud, the guide rod seat, the trigger guard, the backstrap/grip frame, the sight cuts, the magazine well, the ejection port, and the barrel locking lugs (inside the top of the slide in front of the ejection port)
- Barrel, bushing, and barrel link cracks, peening, galling, or corrosion, especially near the muzzle, the chamber mouth, the barrel hood, the locking lugs, or the link pin (or in pistols that use the BHP system instead of the 1911s tilting link, in the cam lug)
- Very loose frame to slide fit, and loose barrel to bushing (or bushing to frame) fit. A little loose is ok, very loose is not.
- Burrs, gouges, ridges, pits, troughs, excessive machining marks, or too much material removed from the feed ramp or barrel throat
- Hammer following or trigger bounce (where the hammer comes down by itself when you drop the slide)
- Improper functioning of the controls: Trigger, hammer, slidestop, magazine catch, safety, or grip safety (trigger doesn't pull smoothly and consistently, hammer doesnt cock crisply, hammer doesn't drop with sufficient force, falls to half cock on release or trigger pull, or bounces back, safety does not engage or disengage properly, safety disengages when the trigger is pulled, safety does not prevent the hammer from falling, Hammer falls when safety is engaged or disengaged. Slide doesn't lock back on an empty magazine, slide doesn't lock when stop is actuated. Slide doesn't drop smoothly when stop is released. Magazine catch doesn't hold, or doesn't release magazine)
- Pistol does not feed or eject properly using snapcaps or dummy cartridges, and the problem isn’t resolved by changing to a known good magazine.
- Improper magazine retention (meaning it does not fully seat and catch, does not drop free, sticks, etc...) with an otherwise good appearing magazine and magazine catch, that isn’t resolved by changing to a different magazine.
- Very loose, worn, damaged, or corroded hard parts; including sights, trigger, magazine release, slide stop, safety, grip safety, firing pin, firing pin stop, hammer, extractor, ejector, plunger tube, guide rod, and mainspring housing,
- Worn or damaged springs
Everything but frame and slide cracks are fixable; to a varying degree of difficulty. In fact even cracks can be fixed, but if the gun isn't extremely rare it's generally not worthwhile.
Most parts on a 1911 are easily replaceable, but may require some fitting for proper function; so a few problems aren't necessarily a show stopper; but you need to know which ones are rejection points, and which are negotiating points. The fact is, most problems with auto pistols are from springs, or magazines (or both). Those are trivial to fix in the case of a 1911.
If a pistol as problems 1 through 4, just walk away; the gun is a money pit, and only suitable for an expert rebuild.
The only time I'd buy a gun in this condition is if the problem was just a bit of barrel to bushing looseness, and the gun was really cheap (because I'd need to replace the barrel and bushing - not cheap)... or maybe if the gun was scrap metal priced, and you wanted it for parts, or as a project gun to increase your skills as a gunsmith.
Oh, and a note for someone who isn't averse to a little gunsmithing work, or a good bargain; there is one specific, common, very small crack that doesn't ruin a 1911:
If there is a small crack in the bridge of metal over the slide stop notch (not the pin hole, the notch in front of the plunger tube); and that crack doesn't extend beyond the corners of the notch, the metal can be machined out, and the frame saved.
Problems 5 through 8, MAY be resolved through simple parts swapping and fitting; or they may not. It takes an expert to be sure. Honestly, if a pistol has any of those problems and you aren’t an expert, qualified to judge what may be wrong, I’d walk away right then.
Problems 9 and 10, presuming they are not indicative of other problems (a cracked slide stop usually means a peened or cracked frame as well for example) can generally be fixed with a simple parts swap and are a reason to discount a gun, but not necessarily to reject it.
Also, just taking a good look at general condition can tell you a lot about the gun. If the general cosmetic condition is poor, or if its “ok” on the surface but a close look shows issues; the gun is probably a beater and you'll want to put it down.
Combine these points, with the simple function check portion of my auto pistol checkout, and you shouldn't be steered wrong.