4 votes now for Watco Danish Oil Finish, including Brad Bachelder as noted by Paul
http://parkerguns.org/forums/showthread.php?t=9779

Rangoon oil has also been recommended for the barrels
http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=413823

Protecting case colors is another issue, and we've had numerous debates here

U.S. makers (no idea re: Lefever) did apply something. Hunter Arms used lacquer, mixed with 1/3 lacquer thinner, applied with cotton balls to protect the case colors.

As Keith said, resulting eventually in this



Ithaca Flues



I vote Renaissance Wax for the case colors
https://restorationproduct.com/shop/renaissance-wax/

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