Looking at the bit it is round, so 3 degrees all the way around, or one side. But i don't know as much as you do so can't be for sure, I don't have a mill........CurtI've been poking around the net and it seems categorizing tapered miils is usually done by just one side. McMaster. MSC. etc. They all list the taper that way.
I wish I knew more about this stuff ....
7 degree would be fine. a little more air flow.It has finally sunk thru my thick skull that they're categorized by the angle on one side only. What tipped it was looking at a 45 degree cutter. Clearly 45 on one side. That would be 90 included but it's still a 45 degree end mill.
And ya might know 6 degrees doesn't seem to be real common. McMaster skips from 5 to 7 for one. But I'm still lookin' ....