Re: Fluting a barrels thats allready been shot
I know a few folks who have air gaged button rifled barrels (Hart, Douglass, Shilen, Schneider, others) before and after fluting them. They all have observed the same stuff. Before fluting, the groove diameters are very uniform.
After fluting about 3/16th inch wide and deep, the groove diameters are smaller starting into the fluted area then open up to a larger diameter than before fluting under the flutes, then go back to less than original groove diameter a bit. Quite a ways from the flutes, groove diameter stays the same.
Accuracy has always been worse after fluting. Well, the bore dimensions went haywire so it's no wonder accuracy went to pot.
And the barrel is always less stiff after fluting than before; you've removed part of the metal that made it as stiff as it was.