The 28926 ejector fixed that problem in my Gen3 G27. My Gen3 G23 doesn't do it with the old 1882 ejector though.
If your Gen4 G23 has the 1882 ejector, I'd upgrade to the 28926. If you still experience the problem with the 28926 ejector, keep that ejector in the gun and try replacing the extractor. Glock's newest extractors are much more likely to be out-of-spec and not move freely enough in the slide.
Since yours is a Gen4, if it has the 1882 ejector in it you could call Glock, speak to the Warranty Service Department, and tell them what the gun is doing and that you want the upgraded parts for your gun. They'll tell you to find a Certified Glock Armorer in your area to install the parts for you. If you can't find one in your area, tell them that and ask that they send you a prepaid shipping label so you can send the gun back to them and have them install the parts. They may or may not agree to give you a prepaid shipping label, it depends which person you talk to.
Your friends who have G23's from '94 and '07 may not need the new ejector. Their problem may be caused by residue built up around the extractor, causing the extractor to not move as freely as it should. For them I'd try detail strip cleaning the internal areas and parts of the slide. I personally use Hoppe's Elite Gun Cleaner and q-tips with special care not to leave any cotton behind inside the slide, then wipe everything dry. If you wipe everything down with oil for corrosion protection, make sure to wipe everything as dry as possible before reassembling the slide, any excess oil in the internals of the slide will collect excess residue and brass shavings and cause various malfunctions.
If detail strip cleaning the slides doesn't work for them, the 28926 ejector should fix the problem. Their guns should have older extractors that were much better quality than Glock's newest extractors. I would NOT replace those extractors.
[ame]http://www.youtube.com/watch?v=7VTIqAMPOco[/ame]
[ame]http://www.youtube.com/watch?v=oV0wDDFV0NY[/ame]
On the following page are some Glock Armorer's Manuals, just scroll down to the "G" section. I learned from the Update Manual and 2009 Manual. The 2009 Manual has a few pages missing, but that info can be found in the Update Manual as well.
http://stevespages.com/page7b.htm
