I have 50 rounds of 2 round balls with a diameter of .600" that I loaded from what Blood Trail posted and longbow also helped. It works good in my double. I have a chance to hunt hogs in Florida with a friend and need input on what gun to use. I have the use of one of 3 shotguns. A Remington 870, a Mossberg 500, or a Mossberg 590A1 all are 3" chambered, cylinder bore, tactical configured with 18.5" barrels. I would use my double but want more rounds in the gun than 2. I have been looking for a 590A1 but come up a dollar short or a day late. Over the years I have used both a Wingmaster 870 and a Mossberg 500A and like both and have take several birds with them. I shoot both about the same but not as good as the SxS, my SASS shotgun.