I know the Remington 870's reputation for reliability. However, I have one that I regularly shoot skeet with out at our farm that seems to jam constantly after firing a few rounds. It refuses to eject the spent shell, usually causing a delay in the fun while I struggle to get it out. The gun is on its second professionally installed extractor pin. My father, a much better shot than me even in his old age , has the same problem when he shoots the gun, so I do not believe i am "short-shucking" it, or whatever term you may use for that. I am losing confidence in this gun. Any suggestions?