I would suspect the ammo more. I have shot my M1/M3's at several shotgun schools over the years. I went throught several hundred rounds over 3 or 4 days with out cleaning between days and had no malfunctions. I did however conduct a intense cleaning procedure at the conclusion of the courses. Remember to use lots of your favorite lube...
Is there any kind of mount out there that will accomodate a surefire type light system, or similar, for an M3 LE gun. I can't seem to find one anywhere. I found several for the M1014, but nothing so far for the M3
Thanks.