An optical connector for terminating an optical fiber comprises a housing configured to mate with a receptacle and a collar body disposed in the housing. The collar body includes a ferrule securely disposed in an opening of the collar body, the ferrule including a central bore that defines an axis, and a housing portion disposed in a generally central portion of the collar body. The housing portion includes an opening to receive a gripping device to grip an optical fiber. The ferrule is axially moveable independent of the axial movement of the optical fiber and gripping device. The optical connector can be thermally balanced over a temperature range of at least 100° C.