Glock getting stuck 3/4 way through full cycle

[Rumpel Felt]

Ok, this has always pissed me off with Glocks and it seems to happen to all of them at one time or another....

It's a KJW G23. I locked the slide back and then released it again but something fucked up. It stopped half way like it's jammed on the hammer or something. It's annoying as hell because I can't fucking see what's going on. I can pull it back all the way and lock it again but I can't fucking realease it past half way! It's pissing me off to no end at it always happened to my KSC G19. I really don't want to break it ramming it this way or that so I'm asking you all....WHAT THE FUCK IS DOING THIS?? And how the fuck do I fix it.