Returning to the original post, can't say I have. But even cleaning barrels is newish to me...As I now just plink for the main part, I'm not obsessed with pin point accuracy.
Can understand why people do it, especially if they hunt/do FT & HFT/target shooting.
And it is, as evert said, of interest if you like playing with mechanical things.
ATB
Bru
Webley Mk3 x2, Falcon & Junior rifles, HW35x2, AirSporter x2, Gold Star, Meteors x2, Diana 25. SMK B19, Webley Senior, Premier, Hurricane x 2, Tempest, Dan Wesson 8", Crosman 3576, Legends PO8.