If it's an American double or pump I would check chamber length and if short have it lengthened to a long forcing cone 2.75 chamber and use it. 5/8 oz loads for the 28 are common in other countries and do a real job on dove from my experience in Argentina. You may be able to find them here in the States. If the gun is a super light Brit or Flues I don't feel qualified to make recomendations.
bill