Frosted bore

[Olle]

Many (maybe most) guns with frosted bores will still shoot very well. Frosting and pitting is often located in the grooves only, and you won't have a problem as long as the lands are fairly smooth and well defined. Some corrosion on the lands won't hurt much either, their function is to guide the bullet and make it spin, so frosting and a few small pits won't hurt the performance. I have shot some guns with deep pitting, and they performed surprisingly well. As a matter of fact, I have one Dreyse 1907 with a pitted bore and one with a perfect bore, and strange as it sounds: The pitted one actually shoots much better.

There are no good ways of removing it, and it's better to leave it alone. It's etched into the surface of the bore so any method you use would require that you remove material from the bore and that will affect the accuracy for sure. I know that some have done it just to make a bad bore look better (like using a patch and coarse polishing compound), but that's for show only and will be detrimental to the accuracy.

You may want to take a closer look though, and make sure the rifling is sharp (which is the most important factor). I have seen some guns where the owner had tried to clean up a bad bore with different methods, and the tell tale sign of this was that the lands were rounded off. I would stay away from a gun like that, especially if I wanted to shoot it.