I have a 10 rounder, california. I had some issues in the beginning, spring is way to touchy, i could only fit 6 Rounds and than the mag would bulge out so bad it wouldn't go on the gun. I kept the mag loaded for a couple days and its been fine since. It doesn't drop free, but none of my mags do. You have to really make sure you get it in the gun, its a little shorter than the full size, so it makes it a little harder to lock in. If you could i would find somebody that would block full size mags for you if possible, if not the 10 rounder will serve its purpose.