All problems I've had with my Combat Commander can be traced to one of three items, not listed:
1) Bad Ammo. Avoid cheap reloads, factory or "baggie brand." If you do go for large numbers at the expense of quality, be aware that your shooting practice is liable to be more for the sake of perfecting grip, sight picture, etc., because you'll have rounds fomr the same box hitting the dirt in front of you and whistling off into the distance...
2) Bad magazines. Acutally, I haven't had this problem, but it is out there...
3) Operator headspace. Failure to fully insert magazine, limp-writsing, buyhing cheap reloads...
Can't blame the gun.