My P40 has issues with loading the last round in the mag. Sometimes it doesn't feed and jams half way in the chamber, or sometimes it skips the last round totally and leaves the cartridge in the mag. This happens about every other mag and it always happens on the last round. I've had this happen with two different mags (new)and with several brands of ammo. I'm presently using Federal Hydrashock 135gr. Anyone have any ideas?