FYI; if you're having FTFeed.
A while back I was having some issues with trying to feed SWC in my .40-10 g20. I ended up fooling around with some wolf +10 and glock 11 coil mag springs. All seemed well. Yesterday I was shooting some 200gr BT HC hand loads that had always worked good (in oem barrel.)and started to get tons of ftfeed with the meplet catching the top of the chamber on the way in. Sure enough I found my mags that had + springs where giving me fits, went back to oem 10coil and all my problems went away. FYI