how to make finger groove like this

Hi,

I was wondering if anyone here could help me in the process of how to make a finger groove like this in an HK G3 bolt? What tools etc

Thanks
Tom

https://www.freeimage.us/image-9AB9_5AF76A43.jpg

A mill and whatever cutter matches the shape of those cuts. I assume a ball was used to make the initial semi oval cut to depth before the grooves were cut.

http://mindworks.shoutwiki.com/wiki/...Mill)#Cutters:4