I would think not enough extractor tension also, or possibly worn/broken extractor claw. Take a loaded round or preferably a snap-cap that has the same weight as a live round and chamber it. Very slowly pull back the slide and watch the round as it's pulled out of the chamber. As it clears the chamber but before it hits the ejector the extractor should have enough tension to hold it flush against the breech face. If it doesn't than it needs more tension.
I don't collect guns, I accumulate them.