On Saturday, April 8, 2017 at 2:53:51 PM UTC-7, Gunner Asch wrote:

It should be mentioned that many..many of the makers of such items
dont machine the entire body..but only a band about 1" wide on each
end..and turn the material in between undersize, so they dont have to
fight the entire length. Which makes a great deal of sense.

I'd always thought that was so the center could take stamped info,
before the final dimensioning. If you're grinding the exterior,
there's no big savings in time or trouble; the whole length is
done in one pass.