There has been a bit of discussion on fire-lapping using papter patched boolits as well as plain cast, jacketed and brass fire-lapping bullets (mine).
Well, here is an example of a rusted bore before and after fire-lapping.
The short bit of muzzle was cut off before commencing fire-lapping and then a bit more was cut off to get to 'good' rifling.
PPCBoo fired in fire-lapped bore with recovered patch.
Boolit fired in mint bore for comparison.
Recovered PPCBoo's. No patch recovered other than a tiny fragment.
The recovered patch fragment is that bit at bottom right.