Try a box of lightfield's. They have given me the best accuracy yet. I am using the lightfield lites 12ga 2 3/4" with 1-1/4oz slug. Zeroed at 100 yards, they are -4.3" at 125.
They are wonderfully accurate and don't nock the snot out of you. If that doesn't work, email T/C and see what slugs they recommend, and what their thoughts are. Hope this helps.