I bought one of those glock 22 15 rd drop free preban mags off of Kieslers. When I load it up full capacity 15+1 and put it in, I notice a knocking noise when I move the gun around. And also the mag dosen't seem to slide in and out as smoothly as my other mags that came with the gun. Is there any problems or is it ok? Whats going on with it?