it probably depends on who's doing it for you. i always touch up the crown when threading a muzzle since i already have spent the time to get the barrel running as close to true as possible in the lathe. touching up the crown only takes a couple minutes.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: wnroscoe</div><div class="ubbcode-body">It only makes good sense to touch up the crown once the muzzle has been indicated in, at least touch up the chamfer if nothing else. </div></div>
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SmallBoreSniper</div><div class="ubbcode-body"> What if the O.D. of a brake is larger or smaller than a O.D. of a barrel? <span style="text-decoration: underline"><span style="font-weight: bold">How does it have a nice flush fit to the barrel? </span></span></div></div>
This is addressed by having a competent gunsmith install it.
I always clean up the crown when shortening a barrel for the client. As for a mismatch in brake vs. barrel diameter, I ask the client if they prefer a tapered mating or the stepped look.
We also determine what finish will be used on the brake..
All this is cleared up with the client before the barrel ever gets mounted in the lathe.
I always recess the bore just a touch deeper than the length of the threads. If your threads are .5 inch long i would recess the bore about .510. Once you thread a barrel the barrel wall can be very thin. Never made sense to me to have a bull barrel taper to a small diameter under the brake. When that wall heats up it can walk (especially with the constant exterior force from the threads pulling at each other). For a .308 i use a .325 reamer. You might lose .5 inch of bore but at least you know your muzzle is good.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C. Dixon</div><div class="ubbcode-body">I too have always made it a practice of cutting a crown whenever threading or working on a muzzle. It's set up anyway and I've done enough of them to know my way works.
Nothing would suck more than taking a completed rifle (coated, blued, painted, etc) to the range only to find out the crown sucks and gun won't shoot.
Now what? You have several more hours (dollars) invested into trying to fix a mistake with a rifle barrel that has finish on it. Now how do you hold onto it without fuggering anything up?
Its darn near impossible.
Even if you don't charge the guy for it, I'd still do it just to avoid a potential headache later.
Makes for good repeat customers. Standard proceedure in my shop.