Thanks for all the replies. I'll try to post a picture of the patterns when I pattern them. The 2.75 inch 00 buck is Cheap wal-mart estate brans shells. The 3 inch 00 buck is Remington Magnum Buckshot. As for slugs, I have a few shells, but only enough to sight in. I'm using a 12 ga Remington 870 w/ 28 inch vent rib barrel w/ Modified or Full choke. The only other barrel I have for it is a 21 inch "Turkey" barrel with extra full choke(.687) Both are smoothbore. P.S. would Mod or Full be better with 00 buck ( I know patterning is everything but which would be better for the large pellets)