The actual standards for the U.S. military are based on body fat percentage, not weight - a bodybuilder, for example, could have very heavy muscles making for a high weight but would still be accepted. For screening purposes weight charts are used as guidelines for who needs more involved body fat screening, but even those differ between services, genders, and age groups. All in all, you can expect the limit to be about 160-170 pounds for someone of your height.