Over the last 2 weekends I've killed 14 gesse with my SBE II and ,675 TERROR tube. I used Federal premium T shot 3.5" mags. Shots ranged from in your face to over 65 yards. I've never had issue shooting large steel thru my terror tube. I bet there's over 1000 rounds of BBB and T shot thru it. Just make sure you aim for the head on those close shots.
Also 1 thing that helped me immensley was I replace the front bead with a fiber optic one off of Tom Knapp's web site the difference is amazing.
Good hunting, Rifleman.