.710 from a .729" twelve bore is a modified choke. A full choke is actually .690" as the normal full choke is 40 'points' or thousanths of choke. OK- they're out 1 thou., it should be .689".
: With all the back boring these days on modern shotguns, .710 could be considered full, I guess. Of that I'm not certain, but of the 40 points of choke for full, I am. I had a double once that had .702" bores, considered improved modified, due to it's .027" choke.
Daryl