Matl steel per ams 6272; hardness per rockwell c20 min and c40 max; 0.794 in. Min and 0.798 in. Max long; 2.9415 in. Min and 2.9425 in. Max od; bore 2.735 in. Min and 2.740 in. Max dia; counterbored 2.8 in. Diameter by 0.095 in. Min and 0.105 in. Max deep