I'm trying to turn a front sight base that will fit a tapered barrel.
After some hand-to-calculator fighting, I came out with a 1/2 degree per
side angle. Start of the band is @.610, the end is @.630, looking at
tapered end mills in Wholesale tool, Grainger, KBC, Enco, and others
shows a decent range of prices, but the corker seems to be the front
diameter. Stock tapered end mill tips are in common sizes, like 3/8,
1/2, 5/8 and 3/4.

Thing is, moving the band rearward gets the band into the diameter of
..623, but the band will be over an inch and a half from the muzzle.

Looking at the iGaging digital protractor, the accuracy is listed as .2
degrees. Resolution is listed as .05 degrees, but look at the accuracy
and we're well into half the value of the desired angle.

How can I set my compound for boring? Angle plates? Adjustable angle?