if you want the tightest pattern possible get ya a box of hevi shot dead coyote and shoot those with a modified choke, a modified choke is the equivalence to a steel full choke or even better get you a full hevi shot choke which is specifically designed for hevi shot.

With the 3.5 inch dead coyote load which has 54 T shot size pellets, from my mossberg 835 with a steel full choke topped with a red dot scope shoots 25% patterns at 100 yard targets which means im getting on average 13 to 14 pellets inside of a 10 inch circle at 100 yards.

Ive shot a few coyotes with this load from 25 to 75 yards and one right near the 100 yard mark. the one at 100 yards ran about 20 yard before expiring with 3 pellets in the neck area and 7 pellets in the rib cage area 4 of the pellets passed completely through. my others had the majority of the pellets between the neck and rib cage with obvious pass through wounds on the otherside.

These may not be the way to go if you want to save pelts but if you want the most range from a shotgun then its deffinately the way to go.

Hevi shot also offers a 3 inch t shot load and recently come out with two 00 buck loads in 2 3/4 inch and 3 inch.