If a bore pit reduces the wall thickness sufficiently, it can lead to a rupture on firing. Bore pits are hard to measure accurately. Light pitting usually isn't a problem, but don't hesitate to call in an expert when in doubt. Pits shouldn't have any dramatic effect on shotgun "accuracy;" pattern "quality" or placement.

Currently, there is no good way to fix pits. Ain't that the pits!!! cry