I go to Snap fitness, the problem is they have no open bench press. I have been using their dumbbells to do dumbbell press in the place of regular bench press. Basically what I want to know is this. I would like to know what my one rep max is, but I don't have the equipment. If I can do 3 sets of 10 reps with the 80lb dumbbells, what would be a good estimate as to what my one rep max would be on a regular bench press?