Octagon to round barrel question.

[Bryan]

I want to take a .22 cal tapered octagon barrel and have it turned partial round. The barrel at the muzzle is .710” how big would it be once turned round?
To clarify what is the diameter of a .710” octagon turned round?

 

[Bryan]

 

[Hood886]

You can keep it at .710 if all you are doing is removing the "triangle" edges to make it round. But really to make finish look the same probably best to take a little more.

Also an important question is are you measuring from tip of triangle to tip or from flat to flat.

https://images.app.goo.gl/TQtTM6CeFQJU86BB9

 

[Bryan]

It is a Green Mountain barrel. I am guessing that they are going across the flats. I guess if I had looked at an octagon closeI could have answered my own question. Thanks