When? - No idea …
Defarb? - Why?
Is it really needed? For what it’s worth, I placed mine next to an original a friend has, at the range just within the last 6-months, and other than my barrel was a tad larger in diameter due to being 58-caliber, and not 54 … everyone at the range (all experience BP builders, collectors & shooters) were actually very impressed with how well it mimicked the original.
Some say the Zoli‘s have poor locks, but the one I have someone must have already been tuned up because it works flawlessly!
Info - Hate to be the one to say it, but type ‘Zoli’ and ‘1803’ into the search feature - like done below - which works well on this site.
PM me if needed, or if you’re looking to acquire one …
https://www.muzzleloadingforum.com/search/1362955/?q=Zoli+1803&o=relevance