Under 400 get a pump, good autos start at much more than $400.

I have to agree with "manwithaplan" . I can't think of any auto's for that price . At least not any I would trust . A pump can be very fast . The recoil from a 12 ga will move your sight picture considerably ,, learn to pump while the gun is in recoil ,, and you'll be just as fast as an auto .