Well, since you have simply cut out parts of the glock flash animation from topglock.com and not actually made the gun 100% realistic, parts are relying on other parts that aren't there. I am working on a 100% realism glock 17, and will post it when I am done.
Only problem is that they don’t have the right collision properties for me when I spawn them, but no biggie. hardest part in real life is just making it in the first place, and as long as the circle gear creator works 100% (it does), everything is good.