Help with beadlocks

I’m in the process of mounting tires on STI HD5 beadlocks, Its says the bolts on the ring are suppose to be tightened to 15 ft. lbs. I just bought an inch pound torque wrench. I’ve tightened them in crisscross pattern starting at 60 inch pounds, I broke a bolt on the first wheel when I got to 100 inch pounds which if i’m correct is 8.33 ft. pounds. I want to use these wheels over Thanksgiving, do any of you have any experience with this that you can share?