I feel like an idiot, but I had a laugh and had to post this. Glocks doesn't have long frame rails like Sigs do. So when I field stripped my 21SF, no biggie getting the gun to come apart. But when I went to put it back together, somehow I got it on the forward rails, but not on the rails furthest to the rear on the gun. I went to rack the slide and it was stuck, before realizing my mistake. Then I kind of panicked and thought, "how the hell am I going to fix this?!" It looked kind of funny, the slide held securely on but crooked and hanging off at the same time. Then after a few seconds i pulled the takedown thing (whatever it is you call the little tabs you pull downwards to field strip the gun) and voila - slide off frame. I have absolutely no idea how I accomplished this, because you figure once the gun rides the front rails it should be good to go all the way back, but maybe it was a bit lopsided or only on securely on 1 side? I guess they idiot proofed this gun though because I was able to get the slide off without harm.