I personally saw a friend of mine shooting a steel challenge stage last month have what he thought was a feeding problem but was in fact a squib load. The only thing that stopped him from firing the next round was the squib stopped the next round from fully chambering just enough to keep the gun from going into battery. Only after trying to tap and rack two rounds did he notice on the second try the gun was just short of going into battery. But the gun did fully eject and fired case and tried to feed the next round after the squib.
Yes, a squib can happen to any gun with one bad round. Absolutely true. But for a squib to happen and cycle the slide and load the next round, though, that takes a bad round, voodoo, and evil pixie dust.
Dave, I want to point out that your friend did exactly what I said someone needed to do to get themselves in trouble with a squib -- he tapped,racked,banged without checking out his problem.
Now, I know you're thinking - A-HA! -- that I said a squib wouldn't cycle the slide, but in your friend's case it did cycle the next round in, which jammed up against the squib. The problem, though, is that your friend TAPPED/RACKED/BANGED without checking that. In fact, he did it twice. Of course there's a live round butted up against the squib after he tapped,racked,banged. HE cycled the next live round in. In all likelihood, his first failure to fire was on the empty case left over from the squib, then that first tap,rack,bang ejected an empty case, and cycled in a live round, which butted up against the squib. Then -- failure to fire. Then -- Tap, rap, bang again. Then -- Failure to fire. Then -- "What's going on? Oh, look, I have a squib."
We had a handloader regular here in the forums last year run some tests to see exactly what it took to produce a squib. In his testing, it took 0.1 grains of powder or no powder at all. With IMR 700-X powder, the slide stopped cycling at 2.0 grains of powder, then he had to reduce the powder charge 95% further, 95% LESS powder than where the slide stopped cycling before he got an actual squib. Then there's the other type of squib, where the powder is compromised in one way or another, and the powder simply burns way too slow and incompletely to generate enough pressure to push the bullet down the barrel, but those also don't create enough pressure to cycle the slide.
Food for thought.
