Round Marks on 1942 byf Luger

[jamese]

all of the above info is true concerning the "END MILL" cutting tool, however those marks appear to me to be caused by the "END MILL" flexing as it cuts the material, which usually results from the speed of the bit as it though the material in relation to the speed in which the bit is turning.

even a sharp bit being pushed through the material faster than the bit can cut will result in the bit flexing leaving gouge marks deeper than the level that the bit is set at.

just my 2 cents