So I've been through 4 or 5 of these things now and every single one of them has CONSISTENTLY double fed. I keep 2 on my range kit now to practice with, but will never run them where it counts. I was just wondering if anyone else has much experience with them-maybe I just had bad luck and got the only 5 shitty mags HK ever made. Add to that the fact that they're super heavy, and I just don't see why anyone would use these things.

Input?