The best buckshot I've found lately is the Federal Vital Shock with the Flite Control wad. We've been qualifying with it for two years and it's really the best 12 gauge 9 shot load I've ever seen. Using standard Remington Police shotguns, it's easy to keep all 9 pellets in the 8-ring of a standard B27 target at 50 yards. Many times we have trouble scoring the targets because once we're though shooting a string of 10 rounds, the target just shows a big ragged hole in the middle of the paper.
That Federal 00 buck load is the best I've seen in a long time. If I were forced to use buckshot for deer, I know what I'd be carrying in the shotgun.