[Shmackey]

I have the same thing, slide is very hard to release on an empty mag....colt mags that came with the firearm. I haven't fired it yet since I got it but won't try to remedy the situation until I try it out first.

Even if you insist on using the slide stop to release the slide, you shouldn't do it on an empty mag because it's not a great practice to thwack it into battery without at cartridge. Besides, the problem goes away when there's a round in the mag.