Any time you change the crown, you run the risk of losing some accuracy. It's a job I'd entrust only to a first rate gunsmith. If your accuracy hasn't been degraded, I'd leave well enough alone!
Marine armorers that I spoke with at Camp Perry six years ago, did the job on a lathe, and only when absolutely necessary. Cleaning rod damage was the prime source of muzzle damage in their opinion.
Our Flag does not fly because the wind blows against it, it is moved instead, by the dying breath of our patriots in uniform. Our Freedom is not free, it's been paid for many times over.
USAF Forward Air Controller, 5th Spl Forces,
An Loc, lll Corps, RVN, 69-70, Vietnam Vet '69-'73