Originally Posted by KY Jon
Location, location, location. Where the thin area is, is just as important as being thin. If near the muzzle, it is less worrisome than if middle or towards the breech. Few would worry about shooting a gun with ten holes drilled in it at the muzzle and calling it ported. .
To quote Mike Orlen after I asked him about pits near the muzzle: "By the time pressure gets to muzzle end, the barrel could be made out of a garden hose." Gil