Damaged inside .25 cal Slug liner. 

No tooling ever touched the rifling.

Pretty cool I see a lot of debris scratches and imperfections I wonder 🤔 how my barrels look on the inside

Have you polished it since? I’m curious if those imperfections will be diminished or gone with a good polish, couldn’t hurt.

Looks like someone has put a wire brush through it? The twist rate doesn’t look very good as well or is it just the camera?