A fiber optic connector sub-assembly includes a ferrule having a front end, a rear end, and a ferrule bore extending between the front and rear ends along a longitudinal axis. The fiber optic connector sub-assembly also includes a bonding agent disposed in the ferrule bore and having first and second ends along the longitudinal axis. The bonding agent has been melted and solidified at the first and second ends without there being an optical fiber present in the ferrule bore.