An insert holder has a holder longitudinal axis defining opposite forward to rearward directions, a holder end surface located at a forward end thereof, and a holder peripheral surface extending circumferentially about the holder longitudinal axis. The insert holder has upper and lower jaws which are spaced apart by a clamping recess recessed in the holder end surface. The upper jaw is resiliently movable with respect to the lower jaw upon rotation around an angled pivot axis. The insert holder includes a forwardly located insert mounting portion which includes a forwardly protruding clamping finger and a forwardly protruding support rib. The clamping recess is defined partially by an elongated recess hinge surface formed on an angled hinge portion. The recess hinge surface includes a first hinge end and a second hinge end, longitudinally spaced apart from one another. The second hinge end is located forward of the first hinge end.