I own a Girsan MC312 semi auto 12ga and I am confused how the gun is patterning with factory chokes. I see 2 different info online about using factory chokes ok with steel shots, then somewhere els online states that it is not ok to use factory chokes with steel shot, now the factory chokes do not have anything written on them but what types they are only, so does that mean I have to buy an after market choke to use for steel shots ? :confused: