I'm at a loss; the first 500-600 round went off without a hiccup. I had no jams, no FTFs. I noticed a few shooting sessions ago I had a FTF, then another; I thought maybe I was limp-wristing it. I was at a loss. Now, today, I was running 3-4 FTFs for every 14 round mag. I'm using the same ammo as the first 500, Winchester white box. The only thought I have is this; I keep my mag full by my night stand, and perhaps this is damaging my mag springs? I did try a different mag on my last 14 shots, and it went off without a hitch. Is anyone else having mag problems? Please let me know, since this is my primary home defense gun, and this type of unreliability is unacceptable. It is also inexplicable, considering the forst 500 went without a hiccup. I love the accuracy, so I'd hate to sell it. HELP!!!