I've had a Brownells chamfering tool for around 25 years now, and have used it to crown and recrown dozens of barrels. It works great, in fact one of the recrowns was on a Remington 700 heavy-barrel .223 that is still the most accurate factory rifle I've owned. When the barrel was young it would average 5 shots of its favorite load in 1/4" at 100 yards.
As Rancho Loco said, it ain't rocket surgery.
