RE: JAMMING!!!!
I can already see this turning into a " high brass vs. low brass" debate.
Quality shells should not cause any problems with that gun, regardless of high or low brass shells. And Federal is usually good quality. Get some AA target loads and shoot them. If they still do it, you need to have the gun checked by a gunsmith.
And always remember, pump guns are NOT delicate actions. Rack those slides like you mean it.