Ball nose and mill insert, a ball nose end mill tool body and a ball nose end mill

A ball nose end mill insert comprising an insert body having an axial center axis, two opposed substantially flat insert side surfaces, a peripheral surface joining the two insert side surfaces, wherein the peripheral surface includes two arcuate surfaces at a first axially forward end of the insert and an insert support surface at a second axially rearward end of the insert, the arcuate surfaces extending axially rearward from an axial center area of the first axially forward end and being positioned symmetrically on opposite sides in relation to the axial center area of the insert, peripheral side surfaces adjoining the arcuate surfaces, an insert through hole intersecting said insert side surfaces, said insert support surface including an axial insert support surface having surface portions on opposite sides of the axial center axis of the insert and a radial insert support surface, wherein said axial insert support surface and said radial insert support surface together form an acute angle.