I know that there must be some 3 gun shooters here. I would like to build or buy an 870 for home defence and the occasional 3 gun match. Which barrell/ sight combo would you get. Will the smooth slug barrel with the rifle sights work pretty well. I think I should be lookin at the 18-20' range, am I wrong? How many shots should my gun be able to hold? Any suggestions as to stock design?